001    /*
002     * Copyright 2007-2014 UnboundID Corp.
003     * All Rights Reserved.
004     */
005    /*
006     * Copyright (C) 2008-2014 UnboundID Corp.
007     *
008     * This program is free software; you can redistribute it and/or modify
009     * it under the terms of the GNU General Public License (GPLv2 only)
010     * or the terms of the GNU Lesser General Public License (LGPLv2.1 only)
011     * as published by the Free Software Foundation.
012     *
013     * This program is distributed in the hope that it will be useful,
014     * but WITHOUT ANY WARRANTY; without even the implied warranty of
015     * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
016     * GNU General Public License for more details.
017     *
018     * You should have received a copy of the GNU General Public License
019     * along with this program; if not, see <http://www.gnu.org/licenses>.
020     */
021    package com.unboundid.ldap.sdk;
022    
023    
024    
025    import java.net.Socket;
026    import java.util.ArrayList;
027    import java.util.Collections;
028    import java.util.EnumSet;
029    import java.util.HashSet;
030    import java.util.List;
031    import java.util.Set;
032    import java.util.logging.Level;
033    import java.util.concurrent.LinkedBlockingQueue;
034    import java.util.concurrent.TimeUnit;
035    import java.util.concurrent.atomic.AtomicInteger;
036    import java.util.concurrent.atomic.AtomicReference;
037    
038    import com.unboundid.ldap.protocol.LDAPResponse;
039    import com.unboundid.ldap.sdk.schema.Schema;
040    import com.unboundid.util.ObjectPair;
041    import com.unboundid.util.ThreadSafety;
042    import com.unboundid.util.ThreadSafetyLevel;
043    
044    import static com.unboundid.ldap.sdk.LDAPMessages.*;
045    import static com.unboundid.util.Debug.*;
046    import static com.unboundid.util.StaticUtils.*;
047    import static com.unboundid.util.Validator.*;
048    
049    
050    
051    /**
052     * This class provides an implementation of an LDAP connection pool, which is a
053     * structure that can hold multiple connections established to a given server
054     * that can be reused for multiple operations rather than creating and
055     * destroying connections for each operation.  This connection pool
056     * implementation provides traditional methods for checking out and releasing
057     * connections, but it also provides wrapper methods that make it easy to
058     * perform operations using pooled connections without the need to explicitly
059     * check out or release the connections.
060     * <BR><BR>
061     * Note that both the {@code LDAPConnectionPool} class and the
062     * {@link LDAPConnection} class implement the {@link LDAPInterface} interface.
063     * This is a common interface that defines a number of common methods for
064     * processing LDAP requests.  This means that in many cases, an application can
065     * use an object of type {@link LDAPInterface} rather than
066     * {@link LDAPConnection}, which makes it possible to work with either a single
067     * standalone connection or with a connection pool.
068     * <BR><BR>
069     * <H2>Creating a Connection Pool</H2>
070     * An LDAP connection pool can be created from either a single
071     * {@link LDAPConnection} (for which an appropriate number of copies will be
072     * created to fill out the pool) or using a {@link ServerSet} to create
073     * connections that may span multiple servers.  For example:
074     * <BR><BR>
075     * <PRE>
076     *   // Create a new LDAP connection pool with ten connections established and
077     *   // authenticated to the same server:
078     *   LDAPConnection connection = new LDAPConnection(address, port);
079     *   BindResult bindResult = connection.bind(bindDN, password);
080     *   LDAPConnectionPool connectionPool = new LDAPConnectionPool(connection, 10);
081     *
082     *   // Create a new LDAP connection pool with 10 connections spanning multiple
083     *   // servers using a server set.
084     *   RoundRobinServerSet serverSet = new RoundRobinServerSet(addresses, ports);
085     *   SimpleBindRequest bindRequest = new SimpleBindRequest(bindDN, password);
086     *   LDAPConnectionPool connectionPool =
087     *        new LDAPConnectionPool(serverSet, bindRequest, 10);
088     * </PRE>
089     * Note that in some cases, such as when using StartTLS, it may be necessary to
090     * perform some additional processing when a new connection is created for use
091     * in the connection pool.  In this case, a {@link PostConnectProcessor} should
092     * be provided to accomplish this.  See the documentation for the
093     * {@link StartTLSPostConnectProcessor} class for an example that demonstrates
094     * its use for creating a connection pool with connections secured using
095     * StartTLS.
096     * <BR><BR>
097     * <H2>Processing Operations with a Connection Pool</H2>
098     * If a single operation is to be processed using a connection from the
099     * connection pool, then it can be used without the need to check out or release
100     * a connection or perform any validity checking on the connection.  This can
101     * be accomplished via the {@link LDAPInterface} interface that allows a
102     * connection pool to be treated like a single connection.  For example, to
103     * perform a search using a pooled connection:
104     * <PRE>
105     *   SearchResult searchResult =
106     *        connectionPool.search("dc=example,dc=com", SearchScope.SUB,
107     *                              "(uid=john.doe)");
108     * </PRE>
109     * If an application needs to process multiple operations using a single
110     * connection, then it may be beneficial to obtain a connection from the pool
111     * to use for processing those operations and then return it back to the pool
112     * when it is no longer needed.  This can be done using the
113     * {@link #getConnection} and {@link #releaseConnection} methods.  If during
114     * processing it is determined that the connection is no longer valid, then the
115     * connection should be released back to the pool using the
116     * {@link #releaseDefunctConnection} method, which will ensure that the
117     * connection is closed and a new connection will be established to take its
118     * place in the pool.
119     * <BR><BR>
120     * Note that it is also possible to process multiple operations on a single
121     * connection using the {@link #processRequests} method.  This may be useful if
122     * a fixed set of operations should be processed over the same connection and
123     * none of the subsequent requests depend upon the results of the earlier
124     * operations.
125     * <BR><BR>
126     * Connection pools should generally not be used when performing operations that
127     * may change the state of the underlying connections.  This is particularly
128     * true for bind operations and the StartTLS extended operation, but it may
129     * apply to other types of operations as well.
130     * <BR><BR>
131     * Performing a bind operation using a connection from the pool will invalidate
132     * any previous authentication on that connection, and if that connection is
133     * released back to the pool without first being re-authenticated as the
134     * original user, then subsequent operation attempts may fail or be processed in
135     * an incorrect manner.  Bind operations should only be performed in a
136     * connection pool if the pool is to be used exclusively for processing binds,
137     * if the bind request is specially crafted so that it will not change the
138     * identity of the associated connection (e.g., by including the retain identity
139     * request control in the bind request if using the Commercial Edition of the
140     * LDAP SDK with an UnboundID Directory Server), or if the code using the
141     * connection pool makes sure to re-authenticate the connection as the
142     * appropriate user whenever its identity has been changed.
143     * <BR><BR>
144     * The StartTLS extended operation should never be invoked on a connection which
145     * is part of a connection pool.  It is acceptable for the pool to maintain
146     * connections which have been configured with StartTLS security prior to being
147     * added to the pool (via the use of the {@link StartTLSPostConnectProcessor}).
148     */
149    @ThreadSafety(level=ThreadSafetyLevel.COMPLETELY_THREADSAFE)
150    public final class LDAPConnectionPool
151           extends AbstractConnectionPool
152    {
153      /**
154       * The default health check interval for this connection pool, which is set to
155       * 60000 milliseconds (60 seconds).
156       */
157      private static final long DEFAULT_HEALTH_CHECK_INTERVAL = 60000L;
158    
159    
160    
161      /**
162       * The name of the connection property that may be used to indicate that a
163       * particular connection should have a different maximum connection age than
164       * the default for this pool.
165       */
166      static final String ATTACHMENT_NAME_MAX_CONNECTION_AGE =
167           LDAPConnectionPool.class.getName() + ".maxConnectionAge";
168    
169    
170    
171      // A counter used to keep track of the number of times that the pool failed to
172      // replace a defunct connection.  It may also be initialized to the difference
173      // between the initial and maximum number of connections that should be
174      // included in the pool.
175      private final AtomicInteger failedReplaceCount;
176    
177      // The types of operations that should be retried if they fail in a manner
178      // that may be the result of a connection that is no longer valid.
179      private final AtomicReference<Set<OperationType>> retryOperationTypes;
180    
181      // Indicates whether this connection pool has been closed.
182      private volatile boolean closed;
183    
184      // Indicates whether to create a new connection if necessary rather than
185      // waiting for a connection to become available.
186      private boolean createIfNecessary;
187    
188      // Indicates whether to check the connection age when releasing a connection
189      // back to the pool.
190      private volatile boolean checkConnectionAgeOnRelease;
191    
192      // Indicates whether health check processing for connections in synchronous
193      // mode should include attempting to read with a very short timeout to attempt
194      // to detect closures and unsolicited notifications in a more timely manner.
195      private volatile boolean trySynchronousReadDuringHealthCheck;
196    
197      // The bind request to use to perform authentication whenever a new connection
198      // is established.
199      private final BindRequest bindRequest;
200    
201      // The number of connections to be held in this pool.
202      private final int numConnections;
203    
204      // The health check implementation that should be used for this connection
205      // pool.
206      private LDAPConnectionPoolHealthCheck healthCheck;
207    
208      // The thread that will be used to perform periodic background health checks
209      // for this connection pool.
210      private final LDAPConnectionPoolHealthCheckThread healthCheckThread;
211    
212      // The statistics for this connection pool.
213      private final LDAPConnectionPoolStatistics poolStatistics;
214    
215      // The set of connections that are currently available for use.
216      private final LinkedBlockingQueue<LDAPConnection> availableConnections;
217    
218      // The length of time in milliseconds between periodic health checks against
219      // the available connections in this pool.
220      private volatile long healthCheckInterval;
221    
222      // The time that the last expired connection was closed.
223      private volatile long lastExpiredDisconnectTime;
224    
225      // The maximum length of time in milliseconds that a connection should be
226      // allowed to be established before terminating and re-establishing the
227      // connection.
228      private volatile long maxConnectionAge;
229    
230      // The maximum connection age that should be used for connections created to
231      // replace connections that are released as defunct.
232      private volatile Long maxDefunctReplacementConnectionAge;
233    
234      // The maximum length of time in milliseconds to wait for a connection to be
235      // available.
236      private long maxWaitTime;
237    
238      // The minimum length of time in milliseconds that must pass between
239      // disconnects of connections that have exceeded the maximum connection age.
240      private volatile long minDisconnectInterval;
241    
242      // The schema that should be shared for connections in this pool, along with
243      // its expiration time.
244      private volatile ObjectPair<Long,Schema> pooledSchema;
245    
246      // The post-connect processor for this connection pool, if any.
247      private final PostConnectProcessor postConnectProcessor;
248    
249      // The server set to use for establishing connections for use by this pool.
250      private final ServerSet serverSet;
251    
252      // The user-friendly name assigned to this connection pool.
253      private String connectionPoolName;
254    
255    
256    
257    
258      /**
259       * Creates a new LDAP connection pool with up to the specified number of
260       * connections, created as clones of the provided connection.  Initially, only
261       * the provided connection will be included in the pool, but additional
262       * connections will be created as needed until the pool has reached its full
263       * capacity, at which point the create if necessary and max wait time settings
264       * will be used to determine how to behave if a connection is requested but
265       * none are available.
266       *
267       * @param  connection      The connection to use to provide the template for
268       *                         the other connections to be created.  This
269       *                         connection will be included in the pool.  It must
270       *                         not be {@code null}, and it must be established to
271       *                         the target server.  It does not necessarily need to
272       *                         be authenticated if all connections in the pool are
273       *                         to be unauthenticated.
274       * @param  numConnections  The total number of connections that should be
275       *                         created in the pool.  It must be greater than or
276       *                         equal to one.
277       *
278       * @throws  LDAPException  If the provided connection cannot be used to
279       *                         initialize the pool, or if a problem occurs while
280       *                         attempting to establish any of the connections.  If
281       *                         this is thrown, then all connections associated
282       *                         with the pool (including the one provided as an
283       *                         argument) will be closed.
284       */
285      public LDAPConnectionPool(final LDAPConnection connection,
286                                final int numConnections)
287             throws LDAPException
288      {
289        this(connection, 1, numConnections, null);
290      }
291    
292    
293    
294      /**
295       * Creates a new LDAP connection pool with the specified number of
296       * connections, created as clones of the provided connection.
297       *
298       * @param  connection          The connection to use to provide the template
299       *                             for the other connections to be created.  This
300       *                             connection will be included in the pool.  It
301       *                             must not be {@code null}, and it must be
302       *                             established to the target server.  It does not
303       *                             necessarily need to be authenticated if all
304       *                             connections in the pool are to be
305       *                             unauthenticated.
306       * @param  initialConnections  The number of connections to initially
307       *                             establish when the pool is created.  It must be
308       *                             greater than or equal to one.
309       * @param  maxConnections      The maximum number of connections that should
310       *                             be maintained in the pool.  It must be greater
311       *                             than or equal to the initial number of
312       *                             connections.
313       *
314       * @throws  LDAPException  If the provided connection cannot be used to
315       *                         initialize the pool, or if a problem occurs while
316       *                         attempting to establish any of the connections.  If
317       *                         this is thrown, then all connections associated
318       *                         with the pool (including the one provided as an
319       *                         argument) will be closed.
320       */
321      public LDAPConnectionPool(final LDAPConnection connection,
322                                final int initialConnections,
323                                final int maxConnections)
324             throws LDAPException
325      {
326        this(connection, initialConnections, maxConnections, null);
327      }
328    
329    
330    
331      /**
332       * Creates a new LDAP connection pool with the specified number of
333       * connections, created as clones of the provided connection.
334       *
335       * @param  connection            The connection to use to provide the template
336       *                               for the other connections to be created.
337       *                               This connection will be included in the pool.
338       *                               It must not be {@code null}, and it must be
339       *                               established to the target server.  It does
340       *                               not necessarily need to be authenticated if
341       *                               all connections in the pool are to be
342       *                               unauthenticated.
343       * @param  initialConnections    The number of connections to initially
344       *                               establish when the pool is created.  It must
345       *                               be greater than or equal to one.
346       * @param  maxConnections        The maximum number of connections that should
347       *                               be maintained in the pool.  It must be
348       *                               greater than or equal to the initial number
349       *                               of connections.
350       * @param  postConnectProcessor  A processor that should be used to perform
351       *                               any post-connect processing for connections
352       *                               in this pool.  It may be {@code null} if no
353       *                               special processing is needed.  Note that this
354       *                               processing will not be invoked on the
355       *                               provided connection that will be used as the
356       *                               first connection in the pool.
357       *
358       * @throws  LDAPException  If the provided connection cannot be used to
359       *                         initialize the pool, or if a problem occurs while
360       *                         attempting to establish any of the connections.  If
361       *                         this is thrown, then all connections associated
362       *                         with the pool (including the one provided as an
363       *                         argument) will be closed.
364       */
365      public LDAPConnectionPool(final LDAPConnection connection,
366                                final int initialConnections,
367                                final int maxConnections,
368                                final PostConnectProcessor postConnectProcessor)
369             throws LDAPException
370      {
371        this(connection, initialConnections, maxConnections,  postConnectProcessor,
372             true);
373      }
374    
375    
376    
377      /**
378       * Creates a new LDAP connection pool with the specified number of
379       * connections, created as clones of the provided connection.
380       *
381       * @param  connection             The connection to use to provide the
382       *                                template for the other connections to be
383       *                                created.  This connection will be included
384       *                                in the pool.  It must not be {@code null},
385       *                                and it must be established to the target
386       *                                server.  It does not necessarily need to be
387       *                                authenticated if all connections in the pool
388       *                                are to be unauthenticated.
389       * @param  initialConnections     The number of connections to initially
390       *                                establish when the pool is created.  It must
391       *                                be greater than or equal to one.
392       * @param  maxConnections         The maximum number of connections that
393       *                                should be maintained in the pool.  It must
394       *                                be greater than or equal to the initial
395       *                                number of connections.
396       * @param  postConnectProcessor   A processor that should be used to perform
397       *                                any post-connect processing for connections
398       *                                in this pool.  It may be {@code null} if no
399       *                                special processing is needed.  Note that
400       *                                this processing will not be invoked on the
401       *                                provided connection that will be used as the
402       *                                first connection in the pool.
403       * @param  throwOnConnectFailure  If an exception should be thrown if a
404       *                                problem is encountered while attempting to
405       *                                create the specified initial number of
406       *                                connections.  If {@code true}, then the
407       *                                attempt to create the pool will fail.if any
408       *                                connection cannot be established.  If
409       *                                {@code false}, then the pool will be created
410       *                                but may have fewer than the initial number
411       *                                of connections (or possibly no connections).
412       *
413       * @throws  LDAPException  If the provided connection cannot be used to
414       *                         initialize the pool, or if a problem occurs while
415       *                         attempting to establish any of the connections.  If
416       *                         this is thrown, then all connections associated
417       *                         with the pool (including the one provided as an
418       *                         argument) will be closed.
419       */
420      public LDAPConnectionPool(final LDAPConnection connection,
421                                final int initialConnections,
422                                final int maxConnections,
423                                final PostConnectProcessor postConnectProcessor,
424                                final boolean throwOnConnectFailure)
425             throws LDAPException
426      {
427        this(connection, initialConnections, maxConnections, 1,
428             postConnectProcessor, throwOnConnectFailure);
429      }
430    
431    
432    
433      /**
434       * Creates a new LDAP connection pool with the specified number of
435       * connections, created as clones of the provided connection.
436       *
437       * @param  connection             The connection to use to provide the
438       *                                template for the other connections to be
439       *                                created.  This connection will be included
440       *                                in the pool.  It must not be {@code null},
441       *                                and it must be established to the target
442       *                                server.  It does not necessarily need to be
443       *                                authenticated if all connections in the pool
444       *                                are to be unauthenticated.
445       * @param  initialConnections     The number of connections to initially
446       *                                establish when the pool is created.  It must
447       *                                be greater than or equal to one.
448       * @param  maxConnections         The maximum number of connections that
449       *                                should be maintained in the pool.  It must
450       *                                be greater than or equal to the initial
451       *                                number of connections.
452       * @param  initialConnectThreads  The number of concurrent threads to use to
453       *                                establish the initial set of connections.
454       *                                A value greater than one indicates that the
455       *                                attempt to establish connections should be
456       *                                parallelized.
457       * @param  postConnectProcessor   A processor that should be used to perform
458       *                                any post-connect processing for connections
459       *                                in this pool.  It may be {@code null} if no
460       *                                special processing is needed.  Note that
461       *                                this processing will not be invoked on the
462       *                                provided connection that will be used as the
463       *                                first connection in the pool.
464       * @param  throwOnConnectFailure  If an exception should be thrown if a
465       *                                problem is encountered while attempting to
466       *                                create the specified initial number of
467       *                                connections.  If {@code true}, then the
468       *                                attempt to create the pool will fail.if any
469       *                                connection cannot be established.  If
470       *                                {@code false}, then the pool will be created
471       *                                but may have fewer than the initial number
472       *                                of connections (or possibly no connections).
473       *
474       * @throws  LDAPException  If the provided connection cannot be used to
475       *                         initialize the pool, or if a problem occurs while
476       *                         attempting to establish any of the connections.  If
477       *                         this is thrown, then all connections associated
478       *                         with the pool (including the one provided as an
479       *                         argument) will be closed.
480       */
481      public LDAPConnectionPool(final LDAPConnection connection,
482                                final int initialConnections,
483                                final int maxConnections,
484                                final int initialConnectThreads,
485                                final PostConnectProcessor postConnectProcessor,
486                                final boolean throwOnConnectFailure)
487             throws LDAPException
488      {
489        this(connection, initialConnections, maxConnections, initialConnectThreads,
490             postConnectProcessor, throwOnConnectFailure, null);
491      }
492    
493    
494    
495      /**
496       * Creates a new LDAP connection pool with the specified number of
497       * connections, created as clones of the provided connection.
498       *
499       * @param  connection             The connection to use to provide the
500       *                                template for the other connections to be
501       *                                created.  This connection will be included
502       *                                in the pool.  It must not be {@code null},
503       *                                and it must be established to the target
504       *                                server.  It does not necessarily need to be
505       *                                authenticated if all connections in the pool
506       *                                are to be unauthenticated.
507       * @param  initialConnections     The number of connections to initially
508       *                                establish when the pool is created.  It must
509       *                                be greater than or equal to one.
510       * @param  maxConnections         The maximum number of connections that
511       *                                should be maintained in the pool.  It must
512       *                                be greater than or equal to the initial
513       *                                number of connections.
514       * @param  initialConnectThreads  The number of concurrent threads to use to
515       *                                establish the initial set of connections.
516       *                                A value greater than one indicates that the
517       *                                attempt to establish connections should be
518       *                                parallelized.
519       * @param  postConnectProcessor   A processor that should be used to perform
520       *                                any post-connect processing for connections
521       *                                in this pool.  It may be {@code null} if no
522       *                                special processing is needed.  Note that
523       *                                this processing will not be invoked on the
524       *                                provided connection that will be used as the
525       *                                first connection in the pool.
526       * @param  throwOnConnectFailure  If an exception should be thrown if a
527       *                                problem is encountered while attempting to
528       *                                create the specified initial number of
529       *                                connections.  If {@code true}, then the
530       *                                attempt to create the pool will fail.if any
531       *                                connection cannot be established.  If
532       *                                {@code false}, then the pool will be created
533       *                                but may have fewer than the initial number
534       *                                of connections (or possibly no connections).
535       * @param  healthCheck            The health check that should be used for
536       *                                connections in this pool.  It may be
537       *                                {@code null} if the default health check
538       *                                should be used.
539       *
540       * @throws  LDAPException  If the provided connection cannot be used to
541       *                         initialize the pool, or if a problem occurs while
542       *                         attempting to establish any of the connections.  If
543       *                         this is thrown, then all connections associated
544       *                         with the pool (including the one provided as an
545       *                         argument) will be closed.
546       */
547      public LDAPConnectionPool(final LDAPConnection connection,
548                                final int initialConnections,
549                                final int maxConnections,
550                                final int initialConnectThreads,
551                                final PostConnectProcessor postConnectProcessor,
552                                final boolean throwOnConnectFailure,
553                                final LDAPConnectionPoolHealthCheck healthCheck)
554             throws LDAPException
555      {
556        ensureNotNull(connection);
557        ensureTrue(initialConnections >= 1,
558                   "LDAPConnectionPool.initialConnections must be at least 1.");
559        ensureTrue(maxConnections >= initialConnections,
560                   "LDAPConnectionPool.initialConnections must not be greater " +
561                        "than maxConnections.");
562    
563        this.postConnectProcessor = postConnectProcessor;
564    
565        trySynchronousReadDuringHealthCheck = true;
566        healthCheckInterval = DEFAULT_HEALTH_CHECK_INTERVAL;
567        poolStatistics      = new LDAPConnectionPoolStatistics(this);
568        pooledSchema        = null;
569        connectionPoolName  = null;
570        retryOperationTypes = new AtomicReference<Set<OperationType>>(
571             Collections.unmodifiableSet(EnumSet.noneOf(OperationType.class)));
572        numConnections            = maxConnections;
573        availableConnections      =
574             new LinkedBlockingQueue<LDAPConnection>(numConnections);
575    
576        if (! connection.isConnected())
577        {
578          throw new LDAPException(ResultCode.PARAM_ERROR,
579                                  ERR_POOL_CONN_NOT_ESTABLISHED.get());
580        }
581    
582        if (healthCheck == null)
583        {
584          this.healthCheck = new LDAPConnectionPoolHealthCheck();
585        }
586        else
587        {
588          this.healthCheck = healthCheck;
589        }
590    
591    
592        serverSet = new SingleServerSet(connection.getConnectedAddress(),
593                                        connection.getConnectedPort(),
594                                        connection.getLastUsedSocketFactory(),
595                                        connection.getConnectionOptions());
596        bindRequest = connection.getLastBindRequest();
597    
598        final LDAPConnectionOptions opts = connection.getConnectionOptions();
599        if (opts.usePooledSchema())
600        {
601          try
602          {
603            final Schema schema = connection.getSchema();
604            if (schema != null)
605            {
606              connection.setCachedSchema(schema);
607    
608              final long currentTime = System.currentTimeMillis();
609              final long timeout = opts.getPooledSchemaTimeoutMillis();
610              if ((timeout <= 0L) || (timeout+currentTime <= 0L))
611              {
612                pooledSchema = new ObjectPair<Long,Schema>(Long.MAX_VALUE, schema);
613              }
614              else
615              {
616                pooledSchema =
617                     new ObjectPair<Long,Schema>(timeout+currentTime, schema);
618              }
619            }
620          }
621          catch (final Exception e)
622          {
623            debugException(e);
624          }
625        }
626    
627        final List<LDAPConnection> connList;
628        if (initialConnectThreads > 1)
629        {
630          connList = Collections.synchronizedList(
631               new ArrayList<LDAPConnection>(initialConnections));
632          final ParallelPoolConnector connector = new ParallelPoolConnector(this,
633               connList, initialConnections, initialConnectThreads,
634               throwOnConnectFailure);
635          connector.establishConnections();
636        }
637        else
638        {
639          connList = new ArrayList<LDAPConnection>(initialConnections);
640          connection.setConnectionName(null);
641          connection.setConnectionPool(this);
642          connList.add(connection);
643          for (int i=1; i < initialConnections; i++)
644          {
645            try
646            {
647              connList.add(createConnection());
648            }
649            catch (LDAPException le)
650            {
651              debugException(le);
652    
653              if (throwOnConnectFailure)
654              {
655                for (final LDAPConnection c : connList)
656                {
657                  try
658                  {
659                    c.setDisconnectInfo(DisconnectType.POOL_CREATION_FAILURE, null,
660                         le);
661                    c.terminate(null);
662                  }
663                  catch (Exception e)
664                  {
665                    debugException(e);
666                  }
667                }
668    
669                throw le;
670              }
671            }
672          }
673        }
674    
675        availableConnections.addAll(connList);
676    
677        failedReplaceCount                 =
678             new AtomicInteger(maxConnections - availableConnections.size());
679        createIfNecessary                  = true;
680        checkConnectionAgeOnRelease        = false;
681        maxConnectionAge                   = 0L;
682        maxDefunctReplacementConnectionAge = null;
683        minDisconnectInterval              = 0L;
684        lastExpiredDisconnectTime          = 0L;
685        maxWaitTime                        = 5000L;
686        closed                             = false;
687    
688        healthCheckThread = new LDAPConnectionPoolHealthCheckThread(this);
689        healthCheckThread.start();
690      }
691    
692    
693    
694      /**
695       * Creates a new LDAP connection pool with the specified number of
696       * connections, created using the provided server set.  Initially, only
697       * one will be created and included in the pool, but additional connections
698       * will be created as needed until the pool has reached its full capacity, at
699       * which point the create if necessary and max wait time settings will be used
700       * to determine how to behave if a connection is requested but none are
701       * available.
702       *
703       * @param  serverSet       The server set to use to create the connections.
704       *                         It is acceptable for the server set to create the
705       *                         connections across multiple servers.
706       * @param  bindRequest     The bind request to use to authenticate the
707       *                         connections that are established.  It may be
708       *                         {@code null} if no authentication should be
709       *                         performed on the connections.
710       * @param  numConnections  The total number of connections that should be
711       *                         created in the pool.  It must be greater than or
712       *                         equal to one.
713       *
714       * @throws  LDAPException  If a problem occurs while attempting to establish
715       *                         any of the connections.  If this is thrown, then
716       *                         all connections associated with the pool will be
717       *                         closed.
718       */
719      public LDAPConnectionPool(final ServerSet serverSet,
720                                final BindRequest bindRequest,
721                                final int numConnections)
722             throws LDAPException
723      {
724        this(serverSet, bindRequest, 1, numConnections, null);
725      }
726    
727    
728    
729      /**
730       * Creates a new LDAP connection pool with the specified number of
731       * connections, created using the provided server set.
732       *
733       * @param  serverSet           The server set to use to create the
734       *                             connections.  It is acceptable for the server
735       *                             set to create the connections across multiple
736       *                             servers.
737       * @param  bindRequest         The bind request to use to authenticate the
738       *                             connections that are established.  It may be
739       *                             {@code null} if no authentication should be
740       *                             performed on the connections.
741       * @param  initialConnections  The number of connections to initially
742       *                             establish when the pool is created.  It must be
743       *                             greater than or equal to zero.
744       * @param  maxConnections      The maximum number of connections that should
745       *                             be maintained in the pool.  It must be greater
746       *                             than or equal to the initial number of
747       *                             connections, and must not be zero.
748       *
749       * @throws  LDAPException  If a problem occurs while attempting to establish
750       *                         any of the connections.  If this is thrown, then
751       *                         all connections associated with the pool will be
752       *                         closed.
753       */
754      public LDAPConnectionPool(final ServerSet serverSet,
755                                final BindRequest bindRequest,
756                                final int initialConnections,
757                                final int maxConnections)
758             throws LDAPException
759      {
760        this(serverSet, bindRequest, initialConnections, maxConnections, null);
761      }
762    
763    
764    
765      /**
766       * Creates a new LDAP connection pool with the specified number of
767       * connections, created using the provided server set.
768       *
769       * @param  serverSet             The server set to use to create the
770       *                               connections.  It is acceptable for the server
771       *                               set to create the connections across multiple
772       *                               servers.
773       * @param  bindRequest           The bind request to use to authenticate the
774       *                               connections that are established.  It may be
775       *                               {@code null} if no authentication should be
776       *                               performed on the connections.
777       * @param  initialConnections    The number of connections to initially
778       *                               establish when the pool is created.  It must
779       *                               be greater than or equal to zero.
780       * @param  maxConnections        The maximum number of connections that should
781       *                               be maintained in the pool.  It must be
782       *                               greater than or equal to the initial number
783       *                               of connections, and must not be zero.
784       * @param  postConnectProcessor  A processor that should be used to perform
785       *                               any post-connect processing for connections
786       *                               in this pool.  It may be {@code null} if no
787       *                               special processing is needed.
788       *
789       * @throws  LDAPException  If a problem occurs while attempting to establish
790       *                         any of the connections.  If this is thrown, then
791       *                         all connections associated with the pool will be
792       *                         closed.
793       */
794      public LDAPConnectionPool(final ServerSet serverSet,
795                                final BindRequest bindRequest,
796                                final int initialConnections,
797                                final int maxConnections,
798                                final PostConnectProcessor postConnectProcessor)
799             throws LDAPException
800      {
801        this(serverSet, bindRequest, initialConnections, maxConnections,
802             postConnectProcessor, true);
803      }
804    
805    
806    
807      /**
808       * Creates a new LDAP connection pool with the specified number of
809       * connections, created using the provided server set.
810       *
811       * @param  serverSet              The server set to use to create the
812       *                                connections.  It is acceptable for the
813       *                                server set to create the connections across
814       *                                multiple servers.
815       * @param  bindRequest            The bind request to use to authenticate the
816       *                                connections that are established.  It may be
817       *                                {@code null} if no authentication should be
818       *                                performed on the connections.
819       * @param  initialConnections     The number of connections to initially
820       *                                establish when the pool is created.  It must
821       *                                be greater than or equal to zero.
822       * @param  maxConnections         The maximum number of connections that
823       *                                should be maintained in the pool.  It must
824       *                                be greater than or equal to the initial
825       *                                number of connections, and must not be zero.
826       * @param  postConnectProcessor   A processor that should be used to perform
827       *                                any post-connect processing for connections
828       *                                in this pool.  It may be {@code null} if no
829       *                                special processing is needed.
830       * @param  throwOnConnectFailure  If an exception should be thrown if a
831       *                                problem is encountered while attempting to
832       *                                create the specified initial number of
833       *                                connections.  If {@code true}, then the
834       *                                attempt to create the pool will fail.if any
835       *                                connection cannot be established.  If
836       *                                {@code false}, then the pool will be created
837       *                                but may have fewer than the initial number
838       *                                of connections (or possibly no connections).
839       *
840       * @throws  LDAPException  If a problem occurs while attempting to establish
841       *                         any of the connections and
842       *                         {@code throwOnConnectFailure} is true.  If this is
843       *                         thrown, then all connections associated with the
844       *                         pool will be closed.
845       */
846      public LDAPConnectionPool(final ServerSet serverSet,
847                                final BindRequest bindRequest,
848                                final int initialConnections,
849                                final int maxConnections,
850                                final PostConnectProcessor postConnectProcessor,
851                                final boolean throwOnConnectFailure)
852             throws LDAPException
853      {
854        this(serverSet, bindRequest, initialConnections, maxConnections, 1,
855             postConnectProcessor, throwOnConnectFailure);
856      }
857    
858    
859    
860      /**
861       * Creates a new LDAP connection pool with the specified number of
862       * connections, created using the provided server set.
863       *
864       * @param  serverSet              The server set to use to create the
865       *                                connections.  It is acceptable for the
866       *                                server set to create the connections across
867       *                                multiple servers.
868       * @param  bindRequest            The bind request to use to authenticate the
869       *                                connections that are established.  It may be
870       *                                {@code null} if no authentication should be
871       *                                performed on the connections.
872       * @param  initialConnections     The number of connections to initially
873       *                                establish when the pool is created.  It must
874       *                                be greater than or equal to zero.
875       * @param  maxConnections         The maximum number of connections that
876       *                                should be maintained in the pool.  It must
877       *                                be greater than or equal to the initial
878       *                                number of connections, and must not be zero.
879       * @param  initialConnectThreads  The number of concurrent threads to use to
880       *                                establish the initial set of connections.
881       *                                A value greater than one indicates that the
882       *                                attempt to establish connections should be
883       *                                parallelized.
884       * @param  postConnectProcessor   A processor that should be used to perform
885       *                                any post-connect processing for connections
886       *                                in this pool.  It may be {@code null} if no
887       *                                special processing is needed.
888       * @param  throwOnConnectFailure  If an exception should be thrown if a
889       *                                problem is encountered while attempting to
890       *                                create the specified initial number of
891       *                                connections.  If {@code true}, then the
892       *                                attempt to create the pool will fail.if any
893       *                                connection cannot be established.  If
894       *                                {@code false}, then the pool will be created
895       *                                but may have fewer than the initial number
896       *                                of connections (or possibly no connections).
897       *
898       * @throws  LDAPException  If a problem occurs while attempting to establish
899       *                         any of the connections and
900       *                         {@code throwOnConnectFailure} is true.  If this is
901       *                         thrown, then all connections associated with the
902       *                         pool will be closed.
903       */
904      public LDAPConnectionPool(final ServerSet serverSet,
905                                final BindRequest bindRequest,
906                                final int initialConnections,
907                                final int maxConnections,
908                                final int initialConnectThreads,
909                                final PostConnectProcessor postConnectProcessor,
910                                final boolean throwOnConnectFailure)
911             throws LDAPException
912      {
913        this(serverSet, bindRequest, initialConnections, maxConnections,
914             initialConnectThreads, postConnectProcessor, throwOnConnectFailure,
915             null);
916      }
917    
918    
919    
920      /**
921       * Creates a new LDAP connection pool with the specified number of
922       * connections, created using the provided server set.
923       *
924       * @param  serverSet              The server set to use to create the
925       *                                connections.  It is acceptable for the
926       *                                server set to create the connections across
927       *                                multiple servers.
928       * @param  bindRequest            The bind request to use to authenticate the
929       *                                connections that are established.  It may be
930       *                                {@code null} if no authentication should be
931       *                                performed on the connections.
932       * @param  initialConnections     The number of connections to initially
933       *                                establish when the pool is created.  It must
934       *                                be greater than or equal to zero.
935       * @param  maxConnections         The maximum number of connections that
936       *                                should be maintained in the pool.  It must
937       *                                be greater than or equal to the initial
938       *                                number of connections, and must not be zero.
939       * @param  initialConnectThreads  The number of concurrent threads to use to
940       *                                establish the initial set of connections.
941       *                                A value greater than one indicates that the
942       *                                attempt to establish connections should be
943       *                                parallelized.
944       * @param  postConnectProcessor   A processor that should be used to perform
945       *                                any post-connect processing for connections
946       *                                in this pool.  It may be {@code null} if no
947       *                                special processing is needed.
948       * @param  throwOnConnectFailure  If an exception should be thrown if a
949       *                                problem is encountered while attempting to
950       *                                create the specified initial number of
951       *                                connections.  If {@code true}, then the
952       *                                attempt to create the pool will fail.if any
953       *                                connection cannot be established.  If
954       *                                {@code false}, then the pool will be created
955       *                                but may have fewer than the initial number
956       *                                of connections (or possibly no connections).
957       * @param  healthCheck            The health check that should be used for
958       *                                connections in this pool.  It may be
959       *                                {@code null} if the default health check
960       *                                should be used.
961       *
962       * @throws  LDAPException  If a problem occurs while attempting to establish
963       *                         any of the connections and
964       *                         {@code throwOnConnectFailure} is true.  If this is
965       *                         thrown, then all connections associated with the
966       *                         pool will be closed.
967       */
968      public LDAPConnectionPool(final ServerSet serverSet,
969                                final BindRequest bindRequest,
970                                final int initialConnections,
971                                final int maxConnections,
972                                final int initialConnectThreads,
973                                final PostConnectProcessor postConnectProcessor,
974                                final boolean throwOnConnectFailure,
975                                final LDAPConnectionPoolHealthCheck healthCheck)
976             throws LDAPException
977      {
978        ensureNotNull(serverSet);
979        ensureTrue(initialConnections >= 0,
980                   "LDAPConnectionPool.initialConnections must be greater than " +
981                        "or equal to 0.");
982        ensureTrue(maxConnections > 0,
983                   "LDAPConnectionPool.maxConnections must be greater than 0.");
984        ensureTrue(maxConnections >= initialConnections,
985                   "LDAPConnectionPool.initialConnections must not be greater " +
986                        "than maxConnections.");
987    
988        this.serverSet            = serverSet;
989        this.bindRequest          = bindRequest;
990        this.postConnectProcessor = postConnectProcessor;
991    
992        trySynchronousReadDuringHealthCheck = false;
993        healthCheckInterval = DEFAULT_HEALTH_CHECK_INTERVAL;
994        poolStatistics      = new LDAPConnectionPoolStatistics(this);
995        pooledSchema        = null;
996        connectionPoolName  = null;
997        retryOperationTypes = new AtomicReference<Set<OperationType>>(
998             Collections.unmodifiableSet(EnumSet.noneOf(OperationType.class)));
999    
1000        if (healthCheck == null)
1001        {
1002          this.healthCheck = new LDAPConnectionPoolHealthCheck();
1003        }
1004        else
1005        {
1006          this.healthCheck = healthCheck;
1007        }
1008    
1009        final List<LDAPConnection> connList;
1010        if (initialConnectThreads > 1)
1011        {
1012          connList = Collections.synchronizedList(
1013               new ArrayList<LDAPConnection>(initialConnections));
1014          final ParallelPoolConnector connector = new ParallelPoolConnector(this,
1015               connList, initialConnections, initialConnectThreads,
1016               throwOnConnectFailure);
1017          connector.establishConnections();
1018        }
1019        else
1020        {
1021          connList = new ArrayList<LDAPConnection>(initialConnections);
1022          for (int i=0; i < initialConnections; i++)
1023          {
1024            try
1025            {
1026              connList.add(createConnection());
1027            }
1028            catch (LDAPException le)
1029            {
1030              debugException(le);
1031    
1032              if (throwOnConnectFailure)
1033              {
1034                for (final LDAPConnection c : connList)
1035                {
1036                  try
1037                  {
1038                    c.setDisconnectInfo(DisconnectType.POOL_CREATION_FAILURE, null,
1039                         le);
1040                    c.terminate(null);
1041                  } catch (Exception e)
1042                  {
1043                    debugException(e);
1044                  }
1045                }
1046    
1047                throw le;
1048              }
1049            }
1050          }
1051        }
1052    
1053        numConnections = maxConnections;
1054    
1055        availableConnections =
1056             new LinkedBlockingQueue<LDAPConnection>(numConnections);
1057        availableConnections.addAll(connList);
1058    
1059        failedReplaceCount                 =
1060             new AtomicInteger(maxConnections - availableConnections.size());
1061        createIfNecessary                  = true;
1062        checkConnectionAgeOnRelease        = false;
1063        maxConnectionAge                   = 0L;
1064        maxDefunctReplacementConnectionAge = null;
1065        minDisconnectInterval              = 0L;
1066        lastExpiredDisconnectTime          = 0L;
1067        maxWaitTime                        = 5000L;
1068        closed                             = false;
1069    
1070        healthCheckThread = new LDAPConnectionPoolHealthCheckThread(this);
1071        healthCheckThread.start();
1072      }
1073    
1074    
1075    
1076      /**
1077       * Creates a new LDAP connection for use in this pool.
1078       *
1079       * @return  A new connection created for use in this pool.
1080       *
1081       * @throws  LDAPException  If a problem occurs while attempting to establish
1082       *                         the connection.  If a connection had been created,
1083       *                         it will be closed.
1084       */
1085      LDAPConnection createConnection()
1086                     throws LDAPException
1087      {
1088        final LDAPConnection c = serverSet.getConnection(healthCheck);
1089        c.setConnectionPool(this);
1090    
1091        // Auto-reconnect must be disabled for pooled connections, so turn it off
1092        // if the associated connection options have it enabled for some reason.
1093        LDAPConnectionOptions opts = c.getConnectionOptions();
1094        if (opts.autoReconnect())
1095        {
1096          opts = opts.duplicate();
1097          opts.setAutoReconnect(false);
1098          c.setConnectionOptions(opts);
1099        }
1100    
1101        if (postConnectProcessor != null)
1102        {
1103          try
1104          {
1105            postConnectProcessor.processPreAuthenticatedConnection(c);
1106          }
1107          catch (Exception e)
1108          {
1109            debugException(e);
1110    
1111            try
1112            {
1113              poolStatistics.incrementNumFailedConnectionAttempts();
1114              c.setDisconnectInfo(DisconnectType.POOL_CREATION_FAILURE, null, e);
1115              c.terminate(null);
1116            }
1117            catch (Exception e2)
1118            {
1119              debugException(e2);
1120            }
1121    
1122            if (e instanceof LDAPException)
1123            {
1124              throw ((LDAPException) e);
1125            }
1126            else
1127            {
1128              throw new LDAPException(ResultCode.CONNECT_ERROR,
1129                   ERR_POOL_POST_CONNECT_ERROR.get(getExceptionMessage(e)), e);
1130            }
1131          }
1132        }
1133    
1134        try
1135        {
1136          if (bindRequest != null)
1137          {
1138            c.bind(bindRequest.duplicate());
1139          }
1140        }
1141        catch (Exception e)
1142        {
1143          debugException(e);
1144          try
1145          {
1146            poolStatistics.incrementNumFailedConnectionAttempts();
1147            c.setDisconnectInfo(DisconnectType.BIND_FAILED, null, e);
1148            c.terminate(null);
1149          }
1150          catch (Exception e2)
1151          {
1152            debugException(e2);
1153          }
1154    
1155          if (e instanceof LDAPException)
1156          {
1157            throw ((LDAPException) e);
1158          }
1159          else
1160          {
1161            throw new LDAPException(ResultCode.CONNECT_ERROR,
1162                 ERR_POOL_CONNECT_ERROR.get(getExceptionMessage(e)), e);
1163          }
1164        }
1165    
1166        if (postConnectProcessor != null)
1167        {
1168          try
1169          {
1170            postConnectProcessor.processPostAuthenticatedConnection(c);
1171          }
1172          catch (Exception e)
1173          {
1174            debugException(e);
1175            try
1176            {
1177              poolStatistics.incrementNumFailedConnectionAttempts();
1178              c.setDisconnectInfo(DisconnectType.POOL_CREATION_FAILURE, null, e);
1179              c.terminate(null);
1180            }
1181            catch (Exception e2)
1182            {
1183              debugException(e2);
1184            }
1185    
1186            if (e instanceof LDAPException)
1187            {
1188              throw ((LDAPException) e);
1189            }
1190            else
1191            {
1192              throw new LDAPException(ResultCode.CONNECT_ERROR,
1193                   ERR_POOL_POST_CONNECT_ERROR.get(getExceptionMessage(e)), e);
1194            }
1195          }
1196        }
1197    
1198        if (opts.usePooledSchema())
1199        {
1200          final long currentTime = System.currentTimeMillis();
1201          if ((pooledSchema == null) || (currentTime > pooledSchema.getFirst()))
1202          {
1203            try
1204            {
1205              final Schema schema = c.getSchema();
1206              if (schema != null)
1207              {
1208                c.setCachedSchema(schema);
1209    
1210                final long timeout = opts.getPooledSchemaTimeoutMillis();
1211                if ((timeout <= 0L) || (currentTime + timeout <= 0L))
1212                {
1213                  pooledSchema =
1214                       new ObjectPair<Long,Schema>(Long.MAX_VALUE, schema);
1215                }
1216                else
1217                {
1218                  pooledSchema =
1219                       new ObjectPair<Long,Schema>((currentTime+timeout), schema);
1220                }
1221              }
1222            }
1223            catch (final Exception e)
1224            {
1225              debugException(e);
1226    
1227              // There was a problem retrieving the schema from the server, but if
1228              // we have an earlier copy then we can assume it's still valid.
1229              if (pooledSchema != null)
1230              {
1231                c.setCachedSchema(pooledSchema.getSecond());
1232              }
1233            }
1234          }
1235          else
1236          {
1237            c.setCachedSchema(pooledSchema.getSecond());
1238          }
1239        }
1240    
1241        c.setConnectionPoolName(connectionPoolName);
1242        poolStatistics.incrementNumSuccessfulConnectionAttempts();
1243    
1244        return c;
1245      }
1246    
1247    
1248    
1249      /**
1250       * {@inheritDoc}
1251       */
1252      @Override()
1253      public void close()
1254      {
1255        close(true, 1);
1256      }
1257    
1258    
1259    
1260      /**
1261       * {@inheritDoc}
1262       */
1263      @Override()
1264      public void close(final boolean unbind, final int numThreads)
1265      {
1266        closed = true;
1267        healthCheckThread.stopRunning();
1268    
1269        if (numThreads > 1)
1270        {
1271          final ArrayList<LDAPConnection> connList =
1272               new ArrayList<LDAPConnection>(availableConnections.size());
1273          availableConnections.drainTo(connList);
1274    
1275          final ParallelPoolCloser closer =
1276               new ParallelPoolCloser(connList, unbind, numThreads);
1277          closer.closeConnections();
1278        }
1279        else
1280        {
1281          while (true)
1282          {
1283            final LDAPConnection conn = availableConnections.poll();
1284            if (conn == null)
1285            {
1286              return;
1287            }
1288            else
1289            {
1290              poolStatistics.incrementNumConnectionsClosedUnneeded();
1291              conn.setDisconnectInfo(DisconnectType.POOL_CLOSED, null, null);
1292              if (unbind)
1293              {
1294                conn.terminate(null);
1295              }
1296              else
1297              {
1298                conn.setClosed();
1299              }
1300            }
1301          }
1302        }
1303      }
1304    
1305    
1306    
1307      /**
1308       * {@inheritDoc}
1309       */
1310      @Override()
1311      public boolean isClosed()
1312      {
1313        return closed;
1314      }
1315    
1316    
1317    
1318      /**
1319       * Processes a simple bind using a connection from this connection pool, and
1320       * then reverts that authentication by re-binding as the same user used to
1321       * authenticate new connections.  If new connections are unauthenticated, then
1322       * the subsequent bind will be an anonymous simple bind.  This method attempts
1323       * to ensure that processing the provided bind operation does not have a
1324       * lasting impact the authentication state of the connection used to process
1325       * it.
1326       * <BR><BR>
1327       * If the second bind attempt (the one used to restore the authentication
1328       * identity) fails, the connection will be closed as defunct so that a new
1329       * connection will be created to take its place.
1330       *
1331       * @param  bindDN    The bind DN for the simple bind request.
1332       * @param  password  The password for the simple bind request.
1333       * @param  controls  The optional set of controls for the simple bind request.
1334       *
1335       * @return  The result of processing the provided bind operation.
1336       *
1337       * @throws  LDAPException  If the server rejects the bind request, or if a
1338       *                         problem occurs while sending the request or reading
1339       *                         the response.
1340       */
1341      public BindResult bindAndRevertAuthentication(final String bindDN,
1342                                                    final String password,
1343                                                    final Control... controls)
1344             throws LDAPException
1345      {
1346        return bindAndRevertAuthentication(
1347             new SimpleBindRequest(bindDN, password, controls));
1348      }
1349    
1350    
1351    
1352      /**
1353       * Processes the provided bind request using a connection from this connection
1354       * pool, and then reverts that authentication by re-binding as the same user
1355       * used to authenticate new connections.  If new connections are
1356       * unauthenticated, then the subsequent bind will be an anonymous simple bind.
1357       * This method attempts to ensure that processing the provided bind operation
1358       * does not have a lasting impact the authentication state of the connection
1359       * used to process it.
1360       * <BR><BR>
1361       * If the second bind attempt (the one used to restore the authentication
1362       * identity) fails, the connection will be closed as defunct so that a new
1363       * connection will be created to take its place.
1364       *
1365       * @param  bindRequest  The bind request to be processed.  It must not be
1366       *                      {@code null}.
1367       *
1368       * @return  The result of processing the provided bind operation.
1369       *
1370       * @throws  LDAPException  If the server rejects the bind request, or if a
1371       *                         problem occurs while sending the request or reading
1372       *                         the response.
1373       */
1374      public BindResult bindAndRevertAuthentication(final BindRequest bindRequest)
1375             throws LDAPException
1376      {
1377        LDAPConnection conn = getConnection();
1378    
1379        try
1380        {
1381          final BindResult result = conn.bind(bindRequest);
1382          releaseAndReAuthenticateConnection(conn);
1383          return result;
1384        }
1385        catch (final Throwable t)
1386        {
1387          debugException(t);
1388    
1389          if (t instanceof LDAPException)
1390          {
1391            final LDAPException le = (LDAPException) t;
1392    
1393            boolean shouldThrow;
1394            try
1395            {
1396              healthCheck.ensureConnectionValidAfterException(conn, le);
1397    
1398              // The above call will throw an exception if the connection doesn't
1399              // seem to be valid, so if we've gotten here then we should assume
1400              // that it is valid and we will pass the exception onto the client
1401              // without retrying the operation.
1402              releaseAndReAuthenticateConnection(conn);
1403              shouldThrow = true;
1404            }
1405            catch (final Exception e)
1406            {
1407              debugException(e);
1408    
1409              // This implies that the connection is not valid.  If the pool is
1410              // configured to re-try bind operations on a newly-established
1411              // connection, then that will be done later in this method.
1412              // Otherwise, release the connection as defunct and pass the bind
1413              // exception onto the client.
1414              if (! getOperationTypesToRetryDueToInvalidConnections().contains(
1415                         OperationType.BIND))
1416              {
1417                releaseDefunctConnection(conn);
1418                shouldThrow = true;
1419              }
1420              else
1421              {
1422                shouldThrow = false;
1423              }
1424            }
1425    
1426            if (shouldThrow)
1427            {
1428              throw le;
1429            }
1430          }
1431          else
1432          {
1433            releaseDefunctConnection(conn);
1434            throw new LDAPException(ResultCode.LOCAL_ERROR,
1435                 ERR_POOL_OP_EXCEPTION.get(getExceptionMessage(t)), t);
1436          }
1437        }
1438    
1439    
1440        // If we've gotten here, then the bind operation should be re-tried on a
1441        // newly-established connection.
1442        conn = replaceDefunctConnection(conn);
1443    
1444        try
1445        {
1446          final BindResult result = conn.bind(bindRequest);
1447          releaseAndReAuthenticateConnection(conn);
1448          return result;
1449        }
1450        catch (final Throwable t)
1451        {
1452          debugException(t);
1453    
1454          if (t instanceof LDAPException)
1455          {
1456            final LDAPException le = (LDAPException) t;
1457    
1458            try
1459            {
1460              healthCheck.ensureConnectionValidAfterException(conn, le);
1461              releaseAndReAuthenticateConnection(conn);
1462            }
1463            catch (final Exception e)
1464            {
1465              debugException(e);
1466              releaseDefunctConnection(conn);
1467            }
1468    
1469            throw le;
1470          }
1471          else
1472          {
1473            releaseDefunctConnection(conn);
1474            throw new LDAPException(ResultCode.LOCAL_ERROR,
1475                 ERR_POOL_OP_EXCEPTION.get(getExceptionMessage(t)), t);
1476          }
1477        }
1478      }
1479    
1480    
1481    
1482      /**
1483       * {@inheritDoc}
1484       */
1485      @Override()
1486      public LDAPConnection getConnection()
1487             throws LDAPException
1488      {
1489        if (closed)
1490        {
1491          poolStatistics.incrementNumFailedCheckouts();
1492          throw new LDAPException(ResultCode.CONNECT_ERROR,
1493                                  ERR_POOL_CLOSED.get());
1494        }
1495    
1496        LDAPConnection conn = availableConnections.poll();
1497        if (conn != null)
1498        {
1499          if (conn.isConnected())
1500          {
1501            try
1502            {
1503              healthCheck.ensureConnectionValidForCheckout(conn);
1504              poolStatistics.incrementNumSuccessfulCheckoutsWithoutWaiting();
1505              return conn;
1506            }
1507            catch (LDAPException le)
1508            {
1509              debugException(le);
1510            }
1511          }
1512    
1513          handleDefunctConnection(conn);
1514          for (int i=0; i < numConnections; i++)
1515          {
1516            conn = availableConnections.poll();
1517            if (conn == null)
1518            {
1519              break;
1520            }
1521            else if (conn.isConnected())
1522            {
1523              try
1524              {
1525                healthCheck.ensureConnectionValidForCheckout(conn);
1526                poolStatistics.incrementNumSuccessfulCheckoutsWithoutWaiting();
1527                return conn;
1528              }
1529              catch (LDAPException le)
1530              {
1531                debugException(le);
1532                handleDefunctConnection(conn);
1533              }
1534            }
1535            else
1536            {
1537              handleDefunctConnection(conn);
1538            }
1539          }
1540        }
1541    
1542        if (failedReplaceCount.get() > 0)
1543        {
1544          final int newReplaceCount = failedReplaceCount.getAndDecrement();
1545          if (newReplaceCount > 0)
1546          {
1547            try
1548            {
1549              conn = createConnection();
1550              poolStatistics.incrementNumSuccessfulCheckoutsNewConnection();
1551              return conn;
1552            }
1553            catch (LDAPException le)
1554            {
1555              debugException(le);
1556              failedReplaceCount.incrementAndGet();
1557              poolStatistics.incrementNumFailedCheckouts();
1558              throw le;
1559            }
1560          }
1561          else
1562          {
1563            failedReplaceCount.incrementAndGet();
1564            poolStatistics.incrementNumFailedCheckouts();
1565            throw new LDAPException(ResultCode.CONNECT_ERROR,
1566                                    ERR_POOL_NO_CONNECTIONS.get());
1567          }
1568        }
1569    
1570        if (maxWaitTime > 0)
1571        {
1572          try
1573          {
1574            conn = availableConnections.poll(maxWaitTime, TimeUnit.MILLISECONDS);
1575            if (conn != null)
1576            {
1577              try
1578              {
1579                healthCheck.ensureConnectionValidForCheckout(conn);
1580                poolStatistics.incrementNumSuccessfulCheckoutsAfterWaiting();
1581                return conn;
1582              }
1583              catch (LDAPException le)
1584              {
1585                debugException(le);
1586                handleDefunctConnection(conn);
1587              }
1588            }
1589          }
1590          catch (InterruptedException ie)
1591          {
1592            debugException(ie);
1593          }
1594        }
1595    
1596        if (createIfNecessary)
1597        {
1598          try
1599          {
1600            conn = createConnection();
1601            poolStatistics.incrementNumSuccessfulCheckoutsNewConnection();
1602            return conn;
1603          }
1604          catch (LDAPException le)
1605          {
1606            debugException(le);
1607            poolStatistics.incrementNumFailedCheckouts();
1608            throw le;
1609          }
1610        }
1611        else
1612        {
1613          poolStatistics.incrementNumFailedCheckouts();
1614          throw new LDAPException(ResultCode.CONNECT_ERROR,
1615                                  ERR_POOL_NO_CONNECTIONS.get());
1616        }
1617      }
1618    
1619    
1620    
1621      /**
1622       * Attempts to retrieve a connection from the pool that is established to the
1623       * specified server.  Note that this method will only attempt to return an
1624       * existing connection that is currently available, and will not create a
1625       * connection or wait for any checked-out connections to be returned.
1626       *
1627       * @param  host  The address of the server to which the desired connection
1628       *               should be established.  This must not be {@code null}, and
1629       *               this must exactly match the address provided for the initial
1630       *               connection or the {@code ServerSet} used to create the pool.
1631       * @param  port  The port of the server to which the desired connection should
1632       *               be established.
1633       *
1634       * @return  A connection that is established to the specified server, or
1635       *          {@code null} if there are no available connections established to
1636       *          the specified server.
1637       */
1638      public LDAPConnection getConnection(final String host, final int port)
1639      {
1640        if (closed)
1641        {
1642          poolStatistics.incrementNumFailedCheckouts();
1643          return null;
1644        }
1645    
1646        final HashSet<LDAPConnection> examinedConnections =
1647             new HashSet<LDAPConnection>(numConnections);
1648        while (true)
1649        {
1650          final LDAPConnection conn = availableConnections.poll();
1651          if (conn == null)
1652          {
1653            poolStatistics.incrementNumFailedCheckouts();
1654            return null;
1655          }
1656    
1657          if (examinedConnections.contains(conn))
1658          {
1659            availableConnections.offer(conn);
1660            poolStatistics.incrementNumFailedCheckouts();
1661            return null;
1662          }
1663    
1664          if (conn.getConnectedAddress().equals(host) &&
1665              (port == conn.getConnectedPort()))
1666          {
1667            try
1668            {
1669              healthCheck.ensureConnectionValidForCheckout(conn);
1670              poolStatistics.incrementNumSuccessfulCheckoutsWithoutWaiting();
1671              return conn;
1672            }
1673            catch (final LDAPException le)
1674            {
1675              debugException(le);
1676              handleDefunctConnection(conn);
1677              continue;
1678            }
1679          }
1680    
1681          if (availableConnections.offer(conn))
1682          {
1683            examinedConnections.add(conn);
1684          }
1685        }
1686      }
1687    
1688    
1689    
1690      /**
1691       * {@inheritDoc}
1692       */
1693      @Override()
1694      public void releaseConnection(final LDAPConnection connection)
1695      {
1696        if (connection == null)
1697        {
1698          return;
1699        }
1700    
1701        connection.setConnectionPoolName(connectionPoolName);
1702        if (checkConnectionAgeOnRelease && connectionIsExpired(connection))
1703        {
1704          try
1705          {
1706            final LDAPConnection newConnection = createConnection();
1707            if (availableConnections.offer(newConnection))
1708            {
1709              connection.setDisconnectInfo(DisconnectType.POOLED_CONNECTION_EXPIRED,
1710                   null, null);
1711              connection.terminate(null);
1712              poolStatistics.incrementNumConnectionsClosedExpired();
1713              lastExpiredDisconnectTime = System.currentTimeMillis();
1714            }
1715            else
1716            {
1717              newConnection.setDisconnectInfo(
1718                   DisconnectType.POOLED_CONNECTION_UNNEEDED, null, null);
1719              newConnection.terminate(null);
1720              poolStatistics.incrementNumConnectionsClosedUnneeded();
1721            }
1722          }
1723          catch (final LDAPException le)
1724          {
1725            debugException(le);
1726          }
1727          return;
1728        }
1729    
1730        try
1731        {
1732          healthCheck.ensureConnectionValidForRelease(connection);
1733        }
1734        catch (LDAPException le)
1735        {
1736          releaseDefunctConnection(connection);
1737          return;
1738        }
1739    
1740        if (availableConnections.offer(connection))
1741        {
1742          poolStatistics.incrementNumReleasedValid();
1743        }
1744        else
1745        {
1746          // This means that the connection pool is full, which can happen if the
1747          // pool was empty when a request came in to retrieve a connection and
1748          // createIfNecessary was true.  In this case, we'll just close the
1749          // connection since we don't need it any more.
1750          connection.setDisconnectInfo(DisconnectType.POOLED_CONNECTION_UNNEEDED,
1751                                       null, null);
1752          poolStatistics.incrementNumConnectionsClosedUnneeded();
1753          connection.terminate(null);
1754          return;
1755        }
1756    
1757        if (closed)
1758        {
1759          close();
1760        }
1761      }
1762    
1763    
1764    
1765      /**
1766       * Indicates that the provided connection should be removed from the pool,
1767       * and that no new connection should be created to take its place.  This may
1768       * be used to shrink the pool if such functionality is desired.
1769       *
1770       * @param  connection  The connection to be discarded.
1771       */
1772      public void discardConnection(final LDAPConnection connection)
1773      {
1774        if (connection == null)
1775        {
1776          return;
1777        }
1778    
1779        connection.setDisconnectInfo(DisconnectType.POOLED_CONNECTION_UNNEEDED,
1780             null, null);
1781        connection.terminate(null);
1782        poolStatistics.incrementNumConnectionsClosedUnneeded();
1783    
1784        if (availableConnections.remainingCapacity() > 0)
1785        {
1786          final int newReplaceCount = failedReplaceCount.incrementAndGet();
1787          if (newReplaceCount > numConnections)
1788          {
1789            failedReplaceCount.set(numConnections);
1790          }
1791        }
1792      }
1793    
1794    
1795    
1796      /**
1797       * Performs a bind on the provided connection before releasing it back to the
1798       * pool, so that it will be authenticated as the same user as
1799       * newly-established connections.  If newly-established connections are
1800       * unauthenticated, then this method will perform an anonymous simple bind to
1801       * ensure that the resulting connection is unauthenticated.
1802       *
1803       * Releases the provided connection back to this pool.
1804       *
1805       * @param  connection  The connection to be released back to the pool after
1806       *                     being re-authenticated.
1807       */
1808      public void releaseAndReAuthenticateConnection(
1809                       final LDAPConnection connection)
1810      {
1811        if (connection == null)
1812        {
1813          return;
1814        }
1815    
1816        try
1817        {
1818          if (bindRequest == null)
1819          {
1820            connection.bind("", "");
1821          }
1822          else
1823          {
1824            connection.bind(bindRequest);
1825          }
1826    
1827          releaseConnection(connection);
1828        }
1829        catch (final Exception e)
1830        {
1831          debugException(e);
1832          releaseDefunctConnection(connection);
1833        }
1834      }
1835    
1836    
1837    
1838      /**
1839       * {@inheritDoc}
1840       */
1841      @Override()
1842      public void releaseDefunctConnection(final LDAPConnection connection)
1843      {
1844        if (connection == null)
1845        {
1846          return;
1847        }
1848    
1849        connection.setConnectionPoolName(connectionPoolName);
1850        poolStatistics.incrementNumConnectionsClosedDefunct();
1851        handleDefunctConnection(connection);
1852      }
1853    
1854    
1855    
1856      /**
1857       * Performs the real work of terminating a defunct connection and replacing it
1858       * with a new connection if possible.
1859       *
1860       * @param  connection  The defunct connection to be replaced.
1861       *
1862       * @return  The new connection created to take the place of the defunct
1863       *          connection, or {@code null} if no new connection was created.
1864       *          Note that if a connection is returned, it will have already been
1865       *          made available and the caller must not rely on it being unused for
1866       *          any other purpose.
1867       */
1868      private LDAPConnection handleDefunctConnection(
1869                                  final LDAPConnection connection)
1870      {
1871        connection.setDisconnectInfo(DisconnectType.POOLED_CONNECTION_DEFUNCT, null,
1872                                     null);
1873        connection.terminate(null);
1874    
1875        if (closed)
1876        {
1877          return null;
1878        }
1879    
1880        if (createIfNecessary && (availableConnections.remainingCapacity() <= 0))
1881        {
1882          return null;
1883        }
1884    
1885        try
1886        {
1887          final LDAPConnection conn = createConnection();
1888          if (maxDefunctReplacementConnectionAge != null)
1889          {
1890            // Only set the maximum age if there isn't one already set for the
1891            // connection (i.e., because it was defined by the server set).
1892            if (conn.getAttachment(ATTACHMENT_NAME_MAX_CONNECTION_AGE) == null)
1893            {
1894              conn.setAttachment(ATTACHMENT_NAME_MAX_CONNECTION_AGE,
1895                   maxDefunctReplacementConnectionAge);
1896            }
1897          }
1898    
1899          if (! availableConnections.offer(conn))
1900          {
1901            conn.setDisconnectInfo(DisconnectType.POOLED_CONNECTION_UNNEEDED,
1902                                   null, null);
1903            conn.terminate(null);
1904            return null;
1905          }
1906    
1907          return conn;
1908        }
1909        catch (LDAPException le)
1910        {
1911          debugException(le);
1912          final int newReplaceCount = failedReplaceCount.incrementAndGet();
1913          if (newReplaceCount > numConnections)
1914          {
1915            failedReplaceCount.set(numConnections);
1916          }
1917          return null;
1918        }
1919      }
1920    
1921    
1922    
1923      /**
1924       * {@inheritDoc}
1925       */
1926      @Override()
1927      public LDAPConnection replaceDefunctConnection(
1928                                 final LDAPConnection connection)
1929             throws LDAPException
1930      {
1931        connection.setDisconnectInfo(DisconnectType.POOLED_CONNECTION_DEFUNCT, null,
1932                                     null);
1933        connection.terminate(null);
1934    
1935        if (closed)
1936        {
1937          throw new LDAPException(ResultCode.CONNECT_ERROR, ERR_POOL_CLOSED.get());
1938        }
1939    
1940        return createConnection();
1941      }
1942    
1943    
1944    
1945      /**
1946       * {@inheritDoc}
1947       */
1948      @Override()
1949      public Set<OperationType> getOperationTypesToRetryDueToInvalidConnections()
1950      {
1951        return retryOperationTypes.get();
1952      }
1953    
1954    
1955    
1956      /**
1957       * {@inheritDoc}
1958       */
1959      @Override()
1960      public void setRetryFailedOperationsDueToInvalidConnections(
1961                       final Set<OperationType> operationTypes)
1962      {
1963        if ((operationTypes == null) || operationTypes.isEmpty())
1964        {
1965          retryOperationTypes.set(
1966               Collections.unmodifiableSet(EnumSet.noneOf(OperationType.class)));
1967        }
1968        else
1969        {
1970          final EnumSet<OperationType> s = EnumSet.noneOf(OperationType.class);
1971          s.addAll(operationTypes);
1972          retryOperationTypes.set(Collections.unmodifiableSet(s));
1973        }
1974      }
1975    
1976    
1977    
1978      /**
1979       * Indicates whether the provided connection should be considered expired.
1980       *
1981       * @param  connection  The connection for which to make the determination.
1982       *
1983       * @return  {@code true} if the provided connection should be considered
1984       *          expired, or {@code false} if not.
1985       */
1986      private boolean connectionIsExpired(final LDAPConnection connection)
1987      {
1988        // There may be a custom maximum connection age for the connection.  If that
1989        // is the case, then use that custom max age rather than the pool-default
1990        // max age.
1991        final long maxAge;
1992        final Object maxAgeObj =
1993             connection.getAttachment(ATTACHMENT_NAME_MAX_CONNECTION_AGE);
1994        if ((maxAgeObj != null) && (maxAgeObj instanceof Long))
1995        {
1996          maxAge = (Long) maxAgeObj;
1997        }
1998        else
1999        {
2000          maxAge = maxConnectionAge;
2001        }
2002    
2003        // If connection expiration is not enabled, then there is nothing to do.
2004        if (maxAge <= 0L)
2005        {
2006          return false;
2007        }
2008    
2009        // If there is a minimum disconnect interval, then make sure that we have
2010        // not closed another expired connection too recently.
2011        final long currentTime = System.currentTimeMillis();
2012        if ((currentTime - lastExpiredDisconnectTime) < minDisconnectInterval)
2013        {
2014          return false;
2015        }
2016    
2017        // Get the age of the connection and see if it is expired.
2018        final long connectionAge = currentTime - connection.getConnectTime();
2019        return (connectionAge > maxAge);
2020      }
2021    
2022    
2023    
2024      /**
2025       * {@inheritDoc}
2026       */
2027      @Override()
2028      public String getConnectionPoolName()
2029      {
2030        return connectionPoolName;
2031      }
2032    
2033    
2034    
2035      /**
2036       * {@inheritDoc}
2037       */
2038      @Override()
2039      public void setConnectionPoolName(final String connectionPoolName)
2040      {
2041        this.connectionPoolName = connectionPoolName;
2042        for (final LDAPConnection c : availableConnections)
2043        {
2044          c.setConnectionPoolName(connectionPoolName);
2045        }
2046      }
2047    
2048    
2049    
2050      /**
2051       * Indicates whether the connection pool should create a new connection if one
2052       * is requested when there are none available.
2053       *
2054       * @return  {@code true} if a new connection should be created if none are
2055       *          available when a request is received, or {@code false} if an
2056       *          exception should be thrown to indicate that no connection is
2057       *          available.
2058       */
2059      public boolean getCreateIfNecessary()
2060      {
2061        return createIfNecessary;
2062      }
2063    
2064    
2065    
2066      /**
2067       * Specifies whether the connection pool should create a new connection if one
2068       * is requested when there are none available.
2069       *
2070       * @param  createIfNecessary  Specifies whether the connection pool should
2071       *                            create a new connection if one is requested when
2072       *                            there are none available.
2073       */
2074      public void setCreateIfNecessary(final boolean createIfNecessary)
2075      {
2076        this.createIfNecessary = createIfNecessary;
2077      }
2078    
2079    
2080    
2081      /**
2082       * Retrieves the maximum length of time in milliseconds to wait for a
2083       * connection to become available when trying to obtain a connection from the
2084       * pool.
2085       *
2086       * @return  The maximum length of time in milliseconds to wait for a
2087       *          connection to become available when trying to obtain a connection
2088       *          from the pool, or zero to indicate that the pool should not block
2089       *          at all if no connections are available and that it should either
2090       *          create a new connection or throw an exception.
2091       */
2092      public long getMaxWaitTimeMillis()
2093      {
2094        return maxWaitTime;
2095      }
2096    
2097    
2098    
2099      /**
2100       * Specifies the maximum length of time in milliseconds to wait for a
2101       * connection to become available when trying to obtain a connection from the
2102       * pool.
2103       *
2104       * @param  maxWaitTime  The maximum length of time in milliseconds to wait for
2105       *                      a connection to become available when trying to obtain
2106       *                      a connection from the pool.  A value of zero should be
2107       *                      used to indicate that the pool should not block at all
2108       *                      if no connections are available and that it should
2109       *                      either create a new connection or throw an exception.
2110       */
2111      public void setMaxWaitTimeMillis(final long maxWaitTime)
2112      {
2113        if (maxWaitTime > 0L)
2114        {
2115          this.maxWaitTime = maxWaitTime;
2116        }
2117        else
2118        {
2119          this.maxWaitTime = 0L;
2120        }
2121      }
2122    
2123    
2124    
2125      /**
2126       * Retrieves the maximum length of time in milliseconds that a connection in
2127       * this pool may be established before it is closed and replaced with another
2128       * connection.
2129       *
2130       * @return  The maximum length of time in milliseconds that a connection in
2131       *          this pool may be established before it is closed and replaced with
2132       *          another connection, or {@code 0L} if no maximum age should be
2133       *          enforced.
2134       */
2135      public long getMaxConnectionAgeMillis()
2136      {
2137        return maxConnectionAge;
2138      }
2139    
2140    
2141    
2142      /**
2143       * Specifies the maximum length of time in milliseconds that a connection in
2144       * this pool may be established before it should be closed and replaced with
2145       * another connection.
2146       *
2147       * @param  maxConnectionAge  The maximum length of time in milliseconds that a
2148       *                           connection in this pool may be established before
2149       *                           it should be closed and replaced with another
2150       *                           connection.  A value of zero indicates that no
2151       *                           maximum age should be enforced.
2152       */
2153      public void setMaxConnectionAgeMillis(final long maxConnectionAge)
2154      {
2155        if (maxConnectionAge > 0L)
2156        {
2157          this.maxConnectionAge = maxConnectionAge;
2158        }
2159        else
2160        {
2161          this.maxConnectionAge = 0L;
2162        }
2163      }
2164    
2165    
2166    
2167      /**
2168       * Retrieves the maximum connection age that should be used for connections
2169       * that were created in order to replace defunct connections.  It is possible
2170       * to define a custom maximum connection age for these connections to allow
2171       * them to be closed and re-established more quickly to allow for a
2172       * potentially quicker fail-back to a normal state.  Note, that if this
2173       * capability is to be used, then the maximum age for these connections should
2174       * be long enough to allow the problematic server to become available again
2175       * under normal circumstances (e.g., it should be long enough for at least a
2176       * shutdown and restart of the server, plus some overhead for potentially
2177       * performing routine maintenance while the server is offline, or a chance for
2178       * an administrator to be made available that a server has gone down).
2179       *
2180       * @return  The maximum connection age that should be used for connections
2181       *          that were created in order to replace defunct connections, a value
2182       *          of zero to indicate that no maximum age should be enforced, or
2183       *          {@code null} if the value returned by the
2184       *          {@link #getMaxConnectionAgeMillis()} method should be used.
2185       */
2186      public Long getMaxDefunctReplacementConnectionAgeMillis()
2187      {
2188        return maxDefunctReplacementConnectionAge;
2189      }
2190    
2191    
2192    
2193      /**
2194       * Specifies the maximum connection age that should be used for connections
2195       * that were created in order to replace defunct connections.  It is possible
2196       * to define a custom maximum connection age for these connections to allow
2197       * them to be closed and re-established more quickly to allow for a
2198       * potentially quicker fail-back to a normal state.  Note, that if this
2199       * capability is to be used, then the maximum age for these connections should
2200       * be long enough to allow the problematic server to become available again
2201       * under normal circumstances (e.g., it should be long enough for at least a
2202       * shutdown and restart of the server, plus some overhead for potentially
2203       * performing routine maintenance while the server is offline, or a chance for
2204       * an administrator to be made available that a server has gone down).
2205       *
2206       * @param  maxDefunctReplacementConnectionAge  The maximum connection age that
2207       *              should be used for connections that were created in order to
2208       *              replace defunct connections.  It may be zero if no maximum age
2209       *              should be enforced for such connections, or it may be
2210       *              {@code null} if the value returned by the
2211       *              {@link #getMaxConnectionAgeMillis()} method should be used.
2212       */
2213      public void setMaxDefunctReplacementConnectionAgeMillis(
2214                       final Long maxDefunctReplacementConnectionAge)
2215      {
2216        if (maxDefunctReplacementConnectionAge == null)
2217        {
2218          this.maxDefunctReplacementConnectionAge = null;
2219        }
2220        else if (maxDefunctReplacementConnectionAge > 0L)
2221        {
2222          this.maxDefunctReplacementConnectionAge =
2223               maxDefunctReplacementConnectionAge;
2224        }
2225        else
2226        {
2227          this.maxDefunctReplacementConnectionAge = 0L;
2228        }
2229      }
2230    
2231    
2232    
2233      /**
2234       * Indicates whether to check the age of a connection against the configured
2235       * maximum connection age whenever it is released to the pool.  By default,
2236       * connection age is evaluated in the background using the health check
2237       * thread, but it is also possible to configure the pool to additionally
2238       * examine the age of a connection when it is returned to the pool.
2239       * <BR><BR>
2240       * Performing connection age evaluation only in the background will ensure
2241       * that connections are only closed and re-established in a single-threaded
2242       * manner, which helps minimize the load against the target server, but only
2243       * checks connections that are not in use when the health check thread is
2244       * active.  If the pool is configured to also evaluate the connection age when
2245       * connections are returned to the pool, then it may help ensure that the
2246       * maximum connection age is honored more strictly for all connections, but
2247       * in busy applications may lead to cases in which multiple connections are
2248       * closed and re-established simultaneously, which may increase load against
2249       * the directory server.  The {@link #setMinDisconnectIntervalMillis(long)}
2250       * method may be used to help mitigate the potential performance impact of
2251       * closing and re-establishing multiple connections simultaneously.
2252       *
2253       * @return  {@code true} if the connection pool should check connection age in
2254       *          both the background health check thread and when connections are
2255       *          released to the pool, or {@code false} if the connection age
2256       *          should only be checked by the background health check thread.
2257       */
2258      public boolean checkConnectionAgeOnRelease()
2259      {
2260        return checkConnectionAgeOnRelease;
2261      }
2262    
2263    
2264    
2265      /**
2266       * Specifies whether to check the age of a connection against the configured
2267       * maximum connection age whenever it is released to the pool.  By default,
2268       * connection age is evaluated in the background using the health check
2269       * thread, but it is also possible to configure the pool to additionally
2270       * examine the age of a connection when it is returned to the pool.
2271       * <BR><BR>
2272       * Performing connection age evaluation only in the background will ensure
2273       * that connections are only closed and re-established in a single-threaded
2274       * manner, which helps minimize the load against the target server, but only
2275       * checks connections that are not in use when the health check thread is
2276       * active.  If the pool is configured to also evaluate the connection age when
2277       * connections are returned to the pool, then it may help ensure that the
2278       * maximum connection age is honored more strictly for all connections, but
2279       * in busy applications may lead to cases in which multiple connections are
2280       * closed and re-established simultaneously, which may increase load against
2281       * the directory server.  The {@link #setMinDisconnectIntervalMillis(long)}
2282       * method may be used to help mitigate the potential performance impact of
2283       * closing and re-establishing multiple connections simultaneously.
2284       *
2285       * @param  checkConnectionAgeOnRelease  If {@code true}, this indicates that
2286       *                                      the connection pool should check
2287       *                                      connection age in both the background
2288       *                                      health check thread and when
2289       *                                      connections are released to the pool.
2290       *                                      If {@code false}, this indicates that
2291       *                                      the connection pool should check
2292       *                                      connection age only in the background
2293       *                                      health check thread.
2294       */
2295      public void setCheckConnectionAgeOnRelease(
2296                       final boolean checkConnectionAgeOnRelease)
2297      {
2298        this.checkConnectionAgeOnRelease = checkConnectionAgeOnRelease;
2299      }
2300    
2301    
2302    
2303      /**
2304       * Retrieves the minimum length of time in milliseconds that should pass
2305       * between connections closed because they have been established for longer
2306       * than the maximum connection age.
2307       *
2308       * @return  The minimum length of time in milliseconds that should pass
2309       *          between connections closed because they have been established for
2310       *          longer than the maximum connection age, or {@code 0L} if expired
2311       *          connections may be closed as quickly as they are identified.
2312       */
2313      public long getMinDisconnectIntervalMillis()
2314      {
2315        return minDisconnectInterval;
2316      }
2317    
2318    
2319    
2320      /**
2321       * Specifies the minimum length of time in milliseconds that should pass
2322       * between connections closed because they have been established for longer
2323       * than the maximum connection age.
2324       *
2325       * @param  minDisconnectInterval  The minimum length of time in milliseconds
2326       *                                that should pass between connections closed
2327       *                                because they have been established for
2328       *                                longer than the maximum connection age.  A
2329       *                                value less than or equal to zero indicates
2330       *                                that no minimum time should be enforced.
2331       */
2332      public void setMinDisconnectIntervalMillis(final long minDisconnectInterval)
2333      {
2334        if (minDisconnectInterval > 0)
2335        {
2336          this.minDisconnectInterval = minDisconnectInterval;
2337        }
2338        else
2339        {
2340          this.minDisconnectInterval = 0L;
2341        }
2342      }
2343    
2344    
2345    
2346      /**
2347       * {@inheritDoc}
2348       */
2349      @Override()
2350      public LDAPConnectionPoolHealthCheck getHealthCheck()
2351      {
2352        return healthCheck;
2353      }
2354    
2355    
2356    
2357      /**
2358       * Sets the health check implementation for this connection pool.
2359       *
2360       * @param  healthCheck  The health check implementation for this connection
2361       *                      pool.  It must not be {@code null}.
2362       */
2363      public void setHealthCheck(final LDAPConnectionPoolHealthCheck healthCheck)
2364      {
2365        ensureNotNull(healthCheck);
2366        this.healthCheck = healthCheck;
2367      }
2368    
2369    
2370    
2371      /**
2372       * {@inheritDoc}
2373       */
2374      @Override()
2375      public long getHealthCheckIntervalMillis()
2376      {
2377        return healthCheckInterval;
2378      }
2379    
2380    
2381    
2382      /**
2383       * {@inheritDoc}
2384       */
2385      @Override()
2386      public void setHealthCheckIntervalMillis(final long healthCheckInterval)
2387      {
2388        ensureTrue(healthCheckInterval > 0L,
2389             "LDAPConnectionPool.healthCheckInterval must be greater than 0.");
2390        this.healthCheckInterval = healthCheckInterval;
2391        healthCheckThread.wakeUp();
2392      }
2393    
2394    
2395    
2396      /**
2397       * Indicates whether health check processing for connections operating in
2398       * synchronous mode should include attempting to perform a read from each
2399       * connection with a very short timeout.  This can help detect unsolicited
2400       * responses and unexpected connection closures in a more timely manner.  This
2401       * will be ignored for connections not operating in synchronous mode.
2402       *
2403       * @return  {@code true} if health check processing for connections operating
2404       *          in synchronous mode should include a read attempt with a very
2405       *          short timeout, or {@code false} if not.
2406       */
2407      public boolean trySynchronousReadDuringHealthCheck()
2408      {
2409        return trySynchronousReadDuringHealthCheck;
2410      }
2411    
2412    
2413    
2414      /**
2415       * Specifies whether health check processing for connections operating in
2416       * synchronous mode should include attempting to perform a read from each
2417       * connection with a very short timeout.
2418       *
2419       * @param  trySynchronousReadDuringHealthCheck  Indicates whether health check
2420       *                                              processing for connections
2421       *                                              operating in synchronous mode
2422       *                                              should include attempting to
2423       *                                              perform a read from each
2424       *                                              connection with a very short
2425       *                                              timeout.
2426       */
2427      public void setTrySynchronousReadDuringHealthCheck(
2428                       final boolean trySynchronousReadDuringHealthCheck)
2429      {
2430        this.trySynchronousReadDuringHealthCheck =
2431             trySynchronousReadDuringHealthCheck;
2432      }
2433    
2434    
2435    
2436      /**
2437       * {@inheritDoc}
2438       */
2439      @Override()
2440      protected void doHealthCheck()
2441      {
2442        // Create a set used to hold connections that we've already examined.  If we
2443        // encounter the same connection twice, then we know that we don't need to
2444        // do any more work.
2445        final HashSet<LDAPConnection> examinedConnections =
2446             new HashSet<LDAPConnection>(numConnections);
2447    
2448        for (int i=0; i < numConnections; i++)
2449        {
2450          LDAPConnection conn = availableConnections.poll();
2451          if (conn == null)
2452          {
2453            break;
2454          }
2455          else if (examinedConnections.contains(conn))
2456          {
2457            if (! availableConnections.offer(conn))
2458            {
2459              conn.setDisconnectInfo(DisconnectType.POOLED_CONNECTION_UNNEEDED,
2460                                     null, null);
2461              poolStatistics.incrementNumConnectionsClosedUnneeded();
2462              conn.terminate(null);
2463            }
2464            break;
2465          }
2466    
2467          if (! conn.isConnected())
2468          {
2469            conn = handleDefunctConnection(conn);
2470            if (conn != null)
2471            {
2472              examinedConnections.add(conn);
2473            }
2474          }
2475          else
2476          {
2477            if (connectionIsExpired(conn))
2478            {
2479              try
2480              {
2481                final LDAPConnection newConnection = createConnection();
2482                if (availableConnections.offer(newConnection))
2483                {
2484                  examinedConnections.add(newConnection);
2485                  conn.setDisconnectInfo(DisconnectType.POOLED_CONNECTION_EXPIRED,
2486                       null, null);
2487                  conn.terminate(null);
2488                  poolStatistics.incrementNumConnectionsClosedExpired();
2489                  lastExpiredDisconnectTime = System.currentTimeMillis();
2490                  continue;
2491                }
2492                else
2493                {
2494                  newConnection.setDisconnectInfo(
2495                       DisconnectType.POOLED_CONNECTION_UNNEEDED, null, null);
2496                  newConnection.terminate(null);
2497                  poolStatistics.incrementNumConnectionsClosedUnneeded();
2498                }
2499              }
2500              catch (final LDAPException le)
2501              {
2502                debugException(le);
2503              }
2504            }
2505    
2506    
2507            // If the connection is operating in synchronous mode, then try to read
2508            // a message on it using an extremely short timeout.  This can help
2509            // detect a connection closure or unsolicited notification in a more
2510            // timely manner than if we had to wait for the client code to try to
2511            // use the connection.
2512            if (trySynchronousReadDuringHealthCheck && conn.synchronousMode())
2513            {
2514              int previousTimeout = Integer.MIN_VALUE;
2515              Socket s = null;
2516              try
2517              {
2518                s = conn.getConnectionInternals(true).getSocket();
2519                previousTimeout = s.getSoTimeout();
2520                s.setSoTimeout(1);
2521    
2522                final LDAPResponse response = conn.readResponse(0);
2523                if (response instanceof ConnectionClosedResponse)
2524                {
2525                  conn.setDisconnectInfo(DisconnectType.POOLED_CONNECTION_DEFUNCT,
2526                       ERR_POOL_HEALTH_CHECK_CONN_CLOSED.get(), null);
2527                  poolStatistics.incrementNumConnectionsClosedDefunct();
2528                  conn = handleDefunctConnection(conn);
2529                  if (conn != null)
2530                  {
2531                    examinedConnections.add(conn);
2532                  }
2533                  continue;
2534                }
2535                else if (response instanceof ExtendedResult)
2536                {
2537                  // This means we got an unsolicited response.  It could be a
2538                  // notice of disconnection, or it could be something else, but in
2539                  // any case we'll send it to the connection's unsolicited
2540                  // notification handler (if one is defined).
2541                  final UnsolicitedNotificationHandler h = conn.
2542                       getConnectionOptions().getUnsolicitedNotificationHandler();
2543                  if (h != null)
2544                  {
2545                    h.handleUnsolicitedNotification(conn,
2546                         (ExtendedResult) response);
2547                  }
2548                }
2549                else if (response instanceof LDAPResult)
2550                {
2551                  final LDAPResult r = (LDAPResult) response;
2552                  if (r.getResultCode() == ResultCode.SERVER_DOWN)
2553                  {
2554                    conn.setDisconnectInfo(DisconnectType.POOLED_CONNECTION_DEFUNCT,
2555                         ERR_POOL_HEALTH_CHECK_CONN_CLOSED.get(), null);
2556                    poolStatistics.incrementNumConnectionsClosedDefunct();
2557                    conn = handleDefunctConnection(conn);
2558                    if (conn != null)
2559                    {
2560                      examinedConnections.add(conn);
2561                    }
2562                    continue;
2563                  }
2564                }
2565              }
2566              catch (final LDAPException le)
2567              {
2568                if (le.getResultCode() == ResultCode.TIMEOUT)
2569                {
2570                  debugException(Level.FINEST, le);
2571                }
2572                else
2573                {
2574                  debugException(le);
2575                  conn.setDisconnectInfo(DisconnectType.POOLED_CONNECTION_DEFUNCT,
2576                       ERR_POOL_HEALTH_CHECK_READ_FAILURE.get(
2577                            getExceptionMessage(le)), le);
2578                  poolStatistics.incrementNumConnectionsClosedDefunct();
2579                  conn = handleDefunctConnection(conn);
2580                  if (conn != null)
2581                  {
2582                    examinedConnections.add(conn);
2583                  }
2584                  continue;
2585                }
2586              }
2587              catch (final Exception e)
2588              {
2589                debugException(e);
2590                conn.setDisconnectInfo(DisconnectType.POOLED_CONNECTION_DEFUNCT,
2591                     ERR_POOL_HEALTH_CHECK_READ_FAILURE.get(getExceptionMessage(e)),
2592                     e);
2593                poolStatistics.incrementNumConnectionsClosedDefunct();
2594                conn = handleDefunctConnection(conn);
2595                if (conn != null)
2596                {
2597                  examinedConnections.add(conn);
2598                }
2599                continue;
2600              }
2601              finally
2602              {
2603                if (previousTimeout != Integer.MIN_VALUE)
2604                {
2605                  try
2606                  {
2607                    s.setSoTimeout(previousTimeout);
2608                  }
2609                  catch (final Exception e)
2610                  {
2611                    debugException(e);
2612                    conn.setDisconnectInfo(DisconnectType.POOLED_CONNECTION_DEFUNCT,
2613                         null, e);
2614                    poolStatistics.incrementNumConnectionsClosedDefunct();
2615                    conn = handleDefunctConnection(conn);
2616                    if (conn != null)
2617                    {
2618                      examinedConnections.add(conn);
2619                    }
2620                    continue;
2621                  }
2622                }
2623              }
2624            }
2625    
2626            try
2627            {
2628              healthCheck.ensureConnectionValidForContinuedUse(conn);
2629              if (availableConnections.offer(conn))
2630              {
2631                examinedConnections.add(conn);
2632              }
2633              else
2634              {
2635                conn.setDisconnectInfo(DisconnectType.POOLED_CONNECTION_UNNEEDED,
2636                                       null, null);
2637                poolStatistics.incrementNumConnectionsClosedUnneeded();
2638                conn.terminate(null);
2639              }
2640            }
2641            catch (Exception e)
2642            {
2643              debugException(e);
2644              conn = handleDefunctConnection(conn);
2645              if (conn != null)
2646              {
2647                examinedConnections.add(conn);
2648              }
2649            }
2650          }
2651        }
2652      }
2653    
2654    
2655    
2656      /**
2657       * {@inheritDoc}
2658       */
2659      @Override()
2660      public int getCurrentAvailableConnections()
2661      {
2662        return availableConnections.size();
2663      }
2664    
2665    
2666    
2667      /**
2668       * {@inheritDoc}
2669       */
2670      @Override()
2671      public int getMaximumAvailableConnections()
2672      {
2673        return numConnections;
2674      }
2675    
2676    
2677    
2678      /**
2679       * {@inheritDoc}
2680       */
2681      @Override()
2682      public LDAPConnectionPoolStatistics getConnectionPoolStatistics()
2683      {
2684        return poolStatistics;
2685      }
2686    
2687    
2688    
2689      /**
2690       * Closes this connection pool in the event that it becomes unreferenced.
2691       *
2692       * @throws  Throwable  If an unexpected problem occurs.
2693       */
2694      @Override()
2695      protected void finalize()
2696                throws Throwable
2697      {
2698        super.finalize();
2699    
2700        close();
2701      }
2702    
2703    
2704    
2705      /**
2706       * {@inheritDoc}
2707       */
2708      @Override()
2709      public void toString(final StringBuilder buffer)
2710      {
2711        buffer.append("LDAPConnectionPool(");
2712    
2713        final String name = connectionPoolName;
2714        if (name != null)
2715        {
2716          buffer.append("name='");
2717          buffer.append(name);
2718          buffer.append("', ");
2719        }
2720    
2721        buffer.append("serverSet=");
2722        serverSet.toString(buffer);
2723        buffer.append(", maxConnections=");
2724        buffer.append(numConnections);
2725        buffer.append(')');
2726      }
2727    }