jodd.util.cl

Class ExtendedURLClassLoader

java.lang.Object

java.lang.ClassLoader

java.security.SecureClassLoader

java.net.URLClassLoader

jodd.util.cl.ExtendedURLClassLoader

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable

public class ExtendedURLClassLoader
extends java.net.URLClassLoader

Class loader that offers two loading strategies: parent-first and parent-last. Extends URLClassLoader (for now:) to provide just minimal set of modifications.

When parent-last strategy is used, be aware how you use ClassLoaderUtil as it is designed to follow parent-first strategy.

Field Summary

Fields

Modifier and Type	Field and Description
protected java.lang.String[]	loaderPackages
protected java.lang.ClassLoader	parentClassLoader
protected boolean	parentFirst
protected java.lang.String[]	systemPackages

Constructor Summary

Constructors

Constructor and Description
ExtendedURLClassLoader(java.net.URL[] classpath, java.lang.ClassLoader parent) Creates class loader with parent-first loading strategy.
ExtendedURLClassLoader(java.net.URL[] classpath, java.lang.ClassLoader parent, boolean parentFirst) Creates class loader with given loading strategy.

Method Summary

Methods

Modifier and Type	Method and Description
void	addLoaderPackage(java.lang.String... packages) Adds loader packages or package roots to the list of packages which must be loaded using this loader.
void	addSystemPackage(java.lang.String... packages) Adds system packages or package roots to the list of packages which must be loaded on the parent loader.
java.net.URL	getResource(java.lang.String resourceName) Returns a resource using parent-first or parent-last strategy.
java.util.Enumeration<java.net.URL>	getResources(java.lang.String resourceName) Similar to its super method, except local resources are enumerated before parent resources.
protected boolean	isInPackageList(java.lang.String name, java.lang.String[] packages) Returns true if class or resource name matches at least one package root from the list.
protected boolean	isParentFirst(java.lang.String resourceName) Determines if parent-first strategy should be used.
protected java.lang.String[]	joinPackages(java.lang.String[] dest, java.lang.String[] src) Join packages and appends dot to package names if missing.
protected java.lang.Class<?>	loadClass(java.lang.String className, boolean resolve) Loads class using parent-first or parent-last strategy.
void	setParentFirst(boolean parentFirst) Controls whether class lookup is delegated to the parent loader first or after this loader.

Methods inherited from class java.net.URLClassLoader

addURL, close, definePackage, findClass, findResource, findResources, getPermissions, getResourceAsStream, getURLs, newInstance, newInstance

Methods inherited from class java.security.SecureClassLoader

defineClass, defineClass

Methods inherited from class java.lang.ClassLoader

clearAssertionStatus, defineClass, defineClass, defineClass, defineClass, definePackage, findLibrary, findLoadedClass, findSystemClass, getClassLoadingLock, getPackage, getPackages, getParent, getSystemClassLoader, getSystemResource, getSystemResourceAsStream, getSystemResources, loadClass, registerAsParallelCapable, resolveClass, setClassAssertionStatus, setDefaultAssertionStatus, setPackageAssertionStatus, setSigners

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

parentClassLoader

protected java.lang.ClassLoader parentClassLoader

systemPackages

protected java.lang.String[] systemPackages

loaderPackages

protected java.lang.String[] loaderPackages

parentFirst

protected boolean parentFirst

Constructor Detail

ExtendedURLClassLoader

public ExtendedURLClassLoader(java.net.URL[] classpath,
                      java.lang.ClassLoader parent)

Creates class loader with parent-first loading strategy. This is aligned how java class loaders work.

ExtendedURLClassLoader

public ExtendedURLClassLoader(java.net.URL[] classpath,
                      java.lang.ClassLoader parent,
                      boolean parentFirst)

Creates class loader with given loading strategy.

Method Detail

setParentFirst

public void setParentFirst(boolean parentFirst)

Controls whether class lookup is delegated to the parent loader first or after this loader. Use with extreme caution as setting this to false (i.e. to parent-last) violates the class loader hierarchy.

addSystemPackage

public void addSystemPackage(java.lang.String... packages)

Adds system packages or package roots to the list of packages which must be loaded on the parent loader. By default, the list is already populated with JRE packages.

addLoaderPackage

public void addLoaderPackage(java.lang.String... packages)

Adds loader packages or package roots to the list of packages which must be loaded using this loader.

joinPackages

protected java.lang.String[] joinPackages(java.lang.String[] dest,
                              java.lang.String[] src)

Join packages and appends dot to package names if missing.

isInPackageList

protected boolean isInPackageList(java.lang.String name,
                      java.lang.String[] packages)

Returns true if class or resource name matches at least one package root from the list.

isParentFirst

protected boolean isParentFirst(java.lang.String resourceName)

Determines if parent-first strategy should be used.

loadClass

protected java.lang.Class<?> loadClass(java.lang.String className,
                           boolean resolve)
                                throws java.lang.ClassNotFoundException

Loads class using parent-first or parent-last strategy.

Overrides:

loadClass in class java.lang.ClassLoader

Throws:

java.lang.ClassNotFoundException

getResource

public java.net.URL getResource(java.lang.String resourceName)

Returns a resource using parent-first or parent-last strategy.

Overrides:

getResource in class java.lang.ClassLoader

getResources

public java.util.Enumeration<java.net.URL> getResources(java.lang.String resourceName)
                                                 throws java.io.IOException

Similar to its super method, except local resources are enumerated before parent resources.

Overrides:

getResources in class java.lang.ClassLoader

Throws:

java.io.IOException