Module com.carrotsearch.hppc
Package com.carrotsearch.hppc

Class LongShortHashMap

java.lang.Object
com.carrotsearch.hppc.LongShortHashMap
All Implemented Interfaces:
Accountable, LongShortAssociativeContainer, LongShortMap, Preallocable, Cloneable, Iterable<LongShortCursor>
@Generated(date="2024-06-04T15:20:17+0200", value="KTypeVTypeHashMap.java") public class LongShortHashMap extends Object implements LongShortMap, Preallocable, Cloneable, Accountable
A hash map of long to short, implemented using open addressing with linear probing for collision resolution.
See Also:

  • Nested Class Summary

    Nested Classes
    Modifier and Type
    Class
    Description
    final class 
    LongShortHashMap.KeysContainer
    A view of the keys inside this hash map.

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    protected int
    assigned
    The number of stored keys (assigned key slots), excluding the special "empty" key, if any (use size() instead).
    protected boolean
    hasEmptyKey
    Special treatment for the "empty slot" key marker.
    protected int
    iterationSeed
    Seed used to ensure the hash iteration order is different from an iteration to another.
    long[]
    keys
    The array holding keys.
    protected double
    loadFactor
    The load factor for keys.
    protected int
    mask
    Mask for slot scans in keys.
    protected int
    resizeAt
    Expand (rehash) keys when assigned hits this value.
    short[]
    values
    The array holding values.

  • Constructor Summary

    Constructors
    Constructor
    Description
    LongShortHashMap()
    New instance with sane defaults.
    LongShortHashMap(int expectedElements)
    New instance with sane defaults.
    LongShortHashMap(int expectedElements, double loadFactor)
    New instance with the provided defaults.
    LongShortHashMap(LongShortAssociativeContainer container)
    Create a hash map from all key-value pairs of another container.

  • Method Summary

    Modifier and Type
    Method
    Description
    short
    addTo(long key, short incrementValue)
    Adds incrementValue to any existing value for the given key or inserts incrementValue if key did not previously exist.
    protected void
    allocateBuffers(int arraySize)
    Allocate new internal buffers.
    protected void
    allocateThenInsertThenRehash(int slot, long pendingKey, short pendingValue)
    This method is invoked when there is a new key/ value pair to be inserted into the buffers but there is not enough empty slots to do so.
    void
    clear()
    Clear all keys and values in the container.
    LongShortHashMap
    clone()
    boolean
    containsKey(long key)
    Returns true if this container has an association to a value for the given key.
    void
    ensureCapacity(int expectedElements)
    Ensure this container can hold at least the given number of keys (entries) without resizing its buffers.
    protected boolean
    equalElements(LongShortHashMap other)
    Return true if all keys of some other container exist in this container.
    boolean
    equals(Object obj)
    Compares the specified object with this set for equality.
    <T extends LongShortProcedure>
    T
    forEach(T procedure)
    Applies a given procedure to all keys-value pairs in this container.
    static LongShortHashMap
    from(long[] keys, short[] values)
    Creates a hash map from two index-aligned arrays of key-value pairs.
    short
    get(long key)
    short
    getOrDefault(long key, short defaultValue)
    int
    hashCode()
    protected int
    hashKey(long key)
    Returns a hash code for the given key.
    boolean
    indexExists(int index)
    short
    indexGet(int index)
    Returns the value associated with an existing key.
    void
    indexInsert(int index, long key, short value)
    Inserts a key-value pair for a key that is not present in the map.
    int
    indexOf(long key)
    Returns a logical "index" of a given key that can be used to speed up follow-up value setters or getters in certain scenarios (conditional logic).
    short
    indexRemove(int index)
    Removes a key-value pair at an index previously acquired from LongShortMap.indexOf(long).
    short
    indexReplace(int index, short newValue)
    Replaces the value associated with an existing key and returns any previous value stored for that key.
    boolean
    isEmpty()
    Iterator<LongShortCursor>
    iterator()
    Returns a cursor over the entries (key-value pairs) in this map.
    LongShortHashMap.KeysContainer
    keys()
    Returns a specialized view of the keys of this associated container.
    protected int
    nextIterationSeed()
    Provides the next iteration seed used to build the iteration starting slot and offset increment.
    short
    put(long key, short value)
    Place a given key and value in the container.
    int
    putAll(LongShortAssociativeContainer container)
    Puts all keys from another container to this map, replacing the values of existing keys, if such keys are present.
    int
    putAll(Iterable<? extends LongShortCursor> iterable)
    Puts all key/value pairs from a given iterable into this map.
    short
    putOrAdd(long key, short putValue, short incrementValue)
    If key exists, putValue is inserted into the map, otherwise any existing value is incremented by additionValue.
    long
    ramBytesAllocated()
    Allocated memory estimation
    long
    ramBytesUsed()
    Bytes that is actually been used
    protected void
    rehash(long[] fromKeys, short[] fromValues)
    Rehash from old buffers to new buffers.
    void
    release()
    Removes all elements from the collection and additionally releases any internal buffers.
    short
    remove(long key)
    Remove all values at the given key.
    int
    removeAll(LongContainer other)
    Removes all keys (and associated values) present in a given container.
    int
    removeAll(LongPredicate predicate)
    Removes all keys (and associated values) for which the predicate returns true.
    int
    removeAll(LongShortPredicate predicate)
    Removes all keys (and associated values) for which the predicate returns true.
    protected void
    shiftConflictingKeys(int gapSlot)
    Shift all the slot-conflicting keys and values allocated to (and including) slot.
    int
    size()
    String
    toString()
    Convert the contents of this map to a human-friendly string.
    ShortCollection
    values()
    Returns a container view of all values present in this container.
    protected double
    verifyLoadFactor(double loadFactor)
    Validate load factor range and return it.
    String
    visualizeKeyDistribution(int characters)
    Visually depict the distribution of keys.

    Methods inherited from class java.lang.Object

    finalize, getClass, notify, notifyAll, wait, wait, wait

    Methods inherited from interface java.lang.Iterable

    forEach, spliterator

    Methods inherited from interface com.carrotsearch.hppc.LongShortMap

    putIfAbsent

  • Field Details

    • keys

      public long[] keys
      The array holding keys.

    • values

      public short[] values
      The array holding values.

    • assigned

      protected int assigned
      The number of stored keys (assigned key slots), excluding the special "empty" key, if any (use size() instead).
      See Also:

    • mask

      protected int mask
      Mask for slot scans in keys.

    • resizeAt

      protected int resizeAt
      Expand (rehash) keys when assigned hits this value.

    • hasEmptyKey

      protected boolean hasEmptyKey
      Special treatment for the "empty slot" key marker.

    • loadFactor

      protected double loadFactor
      The load factor for keys.

    • iterationSeed

      protected int iterationSeed
      Seed used to ensure the hash iteration order is different from an iteration to another.

  • Constructor Details

    • LongShortHashMap

      public LongShortHashMap()
      New instance with sane defaults.

    • LongShortHashMap

      public LongShortHashMap(int expectedElements)
      New instance with sane defaults.
      Parameters:
      expectedElements - The expected number of elements guaranteed not to cause buffer expansion (inclusive).

    • LongShortHashMap

      public LongShortHashMap(int expectedElements, double loadFactor)
      New instance with the provided defaults.
      Parameters:
      expectedElements - The expected number of elements guaranteed not to cause a rehash (inclusive).
      loadFactor - The load factor for internal buffers. Insane load factors (zero, full capacity) are rejected by verifyLoadFactor(double).

    • LongShortHashMap

      public LongShortHashMap(LongShortAssociativeContainer container)
      Create a hash map from all key-value pairs of another container.

  • Method Details

    • put

      public short put(long key, short value)
      Place a given key and value in the container.
      Specified by:
      put in interface LongShortMap
      Returns:
      The value previously stored under the given key in the map is returned.

    • putAll

      public int putAll(LongShortAssociativeContainer container)
      Puts all keys from another container to this map, replacing the values of existing keys, if such keys are present.
      Specified by:
      putAll in interface LongShortMap
      Returns:
      Returns the number of keys added to the map as a result of this call (not previously present in the map). Values of existing keys are overwritten.

    • putAll

      public int putAll(Iterable<? extends LongShortCursor> iterable)
      Puts all key/value pairs from a given iterable into this map.
      Specified by:
      putAll in interface LongShortMap
      Returns:
      Returns the number of keys added to the map as a result of this call (not previously present in the map). Values of existing keys are overwritten.

    • putOrAdd

      public short putOrAdd(long key, short putValue, short incrementValue)
      If key exists, putValue is inserted into the map, otherwise any existing value is incremented by additionValue.
      Specified by:
      putOrAdd in interface LongShortMap
      Parameters:
      key - The key of the value to adjust.
      putValue - The value to put if key does not exist.
      incrementValue - The value to add to the existing value if key exists.
      Returns:
      Returns the current value associated with key (after changes).

    • addTo

      public short addTo(long key, short incrementValue)
      Adds incrementValue to any existing value for the given key or inserts incrementValue if key did not previously exist.
      Specified by:
      addTo in interface LongShortMap
      Parameters:
      key - The key of the value to adjust.
      incrementValue - The value to put or add to the existing value if key exists.
      Returns:
      Returns the current value associated with key (after changes).

    • remove

      public short remove(long key)
      Remove all values at the given key. The default value for the key type is returned if the value does not exist in the map.
      Specified by:
      remove in interface LongShortMap

    • removeAll

      public int removeAll(LongContainer other)
      Removes all keys (and associated values) present in a given container. An alias to: 
       keys().removeAll(container)
      but with no additional overhead.
      Specified by:
      removeAll in interface LongShortAssociativeContainer
      Returns:
      Returns the number of elements actually removed as a result of this call.

    • removeAll

      public int removeAll(LongShortPredicate predicate)
      Removes all keys (and associated values) for which the predicate returns true.
      Specified by:
      removeAll in interface LongShortAssociativeContainer
      Returns:
      Returns the number of elements actually removed as a result of this call.

    • removeAll

      public int removeAll(LongPredicate predicate)
      Removes all keys (and associated values) for which the predicate returns true.
      Specified by:
      removeAll in interface LongShortAssociativeContainer
      Returns:
      Returns the number of elements actually removed as a result of this call.

    • get

      public short get(long key)
      Specified by:
      get in interface LongShortMap
      Returns:
      Returns the value associated with the given key or the default value for the value type, if the key is not associated with any value. For numeric value types, this default value is 0, for object types it is null.

    • getOrDefault

      public short getOrDefault(long key, short defaultValue)
      Specified by:
      getOrDefault in interface LongShortMap
      Returns:
      Returns the value associated with the given key or the provided default value if the key is not associated with any value.

    • containsKey

      public boolean containsKey(long key)
      Returns true if this container has an association to a value for the given key.
      Specified by:
      containsKey in interface LongShortAssociativeContainer

    • indexOf

      public int indexOf(long key)
      Returns a logical "index" of a given key that can be used to speed up follow-up value setters or getters in certain scenarios (conditional logic).

      The semantics of "indexes" are not strictly defined. Indexes may (and typically won't be) contiguous.

      The index is valid only between map modifications (it will not be affected by read-only operations like iteration or value retrievals).

      Specified by:
      indexOf in interface LongShortMap
      Parameters:
      key - The key to locate in the map.
      Returns:
      A non-negative value of the logical "index" of the key in the map or a negative value if the key did not exist.
      See Also:

    • indexExists

      public boolean indexExists(int index)
      Specified by:
      indexExists in interface LongShortMap
      Parameters:
      index - The index of a given key, as returned from LongShortMap.indexOf(long).
      Returns:
      Returns true if the index corresponds to an existing key or false otherwise. This is equivalent to checking whether the index is a positive value (existing keys) or a negative value (non-existing keys).
      See Also:

    • indexGet

      public short indexGet(int index)
      Returns the value associated with an existing key.
      Specified by:
      indexGet in interface LongShortMap
      Parameters:
      index - The index of an existing key.
      Returns:
      Returns the value currently associated with the key.
      See Also:

    • indexReplace

      public short indexReplace(int index, short newValue)
      Replaces the value associated with an existing key and returns any previous value stored for that key.
      Specified by:
      indexReplace in interface LongShortMap
      Parameters:
      index - The index of an existing key.
      Returns:
      Returns the previous value associated with the key.
      See Also:

    • indexInsert

      public void indexInsert(int index, long key, short value)
      Inserts a key-value pair for a key that is not present in the map. This method may help in avoiding double recalculation of the key's hash.
      Specified by:
      indexInsert in interface LongShortMap
      Parameters:
      index - The index of a previously non-existing key, as returned from LongShortMap.indexOf(long).
      See Also:

    • indexRemove

      public short indexRemove(int index)
      Removes a key-value pair at an index previously acquired from LongShortMap.indexOf(long).
      Specified by:
      indexRemove in interface LongShortMap
      Parameters:
      index - The index of the key to remove, as returned from LongShortMap.indexOf(long).
      Returns:
      Returns the previous value associated with the key.
      See Also:

    • clear

      public void clear()
      Clear all keys and values in the container.
      Specified by:
      clear in interface LongShortMap
      See Also:

    • release

      public void release()
      Removes all elements from the collection and additionally releases any internal buffers. Typically, if the object is to be reused, a simple LongShortMap.clear() should be a better alternative since it'll avoid reallocation.
      Specified by:
      release in interface LongShortMap
      See Also:

    • size

      public int size()
      Specified by:
      size in interface LongShortAssociativeContainer
      Returns:
      Returns the current size (number of assigned keys) in the container.

    • isEmpty

      public boolean isEmpty()
      Specified by:
      isEmpty in interface LongShortAssociativeContainer
      Returns:
      Return true if this hash map contains no assigned keys.

    • hashCode

      public int hashCode()
      Specified by:
      hashCode in interface LongShortMap
      Overrides:
      hashCode in class Object
      Returns:
      A hash code of elements stored in the map. The hash code is defined as a sum of hash codes of keys and values stored within the set). Because sum is commutative, this ensures that different order of elements in a set does not affect the hash code.

    • equals

      public boolean equals(Object obj)
      Compares the specified object with this set for equality. Returns true if and only if the specified object is also a LongShortMap and both objects contains exactly the same key-value pairs.
      Specified by:
      equals in interface LongShortMap
      Overrides:
      equals in class Object

    • equalElements

      protected boolean equalElements(LongShortHashMap other)
      Return true if all keys of some other container exist in this container.

    • ensureCapacity

      public void ensureCapacity(int expectedElements)
      Ensure this container can hold at least the given number of keys (entries) without resizing its buffers.
      Specified by:
      ensureCapacity in interface Preallocable
      Parameters:
      expectedElements - The total number of keys, inclusive.

    • ramBytesAllocated

      public long ramBytesAllocated()
      Description copied from interface: Accountable
      Allocated memory estimation
      Specified by:
      ramBytesAllocated in interface Accountable
      Returns:
      Ram allocated in bytes

    • ramBytesUsed

      public long ramBytesUsed()
      Description copied from interface: Accountable
      Bytes that is actually been used
      Specified by:
      ramBytesUsed in interface Accountable
      Returns:
      Ram used in bytes

    • nextIterationSeed

      protected int nextIterationSeed()
      Provides the next iteration seed used to build the iteration starting slot and offset increment. This method does not need to be synchronized, what matters is that each thread gets a sequence of varying seeds.

    • iterator

      public Iterator<LongShortCursor> iterator()
      Returns a cursor over the entries (key-value pairs) in this map. The iterator is implemented as a cursor and it returns the same cursor instance on every call to Iterator.next(). To read the current key and value use the cursor's public fields. An example is shown below. 
       for (IntShortCursor c : intShortMap) {
   System.out.println("index=" + c.index + " key=" + c.key + " value=" + c.value);
 }

      The index field inside the cursor gives the internal index inside the container's implementation. The interpretation of this index depends on to the container.

      Specified by:
      iterator in interface Iterable<LongShortCursor>
      Specified by:
      iterator in interface LongShortAssociativeContainer

    • forEach

      public <T extends LongShortProcedure> T forEach(T procedure)
      Applies a given procedure to all keys-value pairs in this container. Returns the argument (any subclass of LongShortProcedure. This lets the caller call methods of the argument by chaining the call (even if the argument is an anonymous type) to retrieve computed values.
      Specified by:
      forEach in interface LongShortAssociativeContainer

    • forEach

      public <T extends LongShortPredicate> T forEach(T predicate)
      Applies a given predicate to all keys-value pairs in this container. Returns the argument (any subclass of LongShortPredicate. This lets the caller call methods of the argument by chaining the call (even if the argument is an anonymous type) to retrieve computed values.

      The iteration is continued as long as the predicate returns true.

      Specified by:
      forEach in interface LongShortAssociativeContainer

    • keys

      public LongShortHashMap.KeysContainer keys()
      Returns a specialized view of the keys of this associated container. The view additionally implements ObjectLookupContainer.
      Specified by:
      keys in interface LongShortAssociativeContainer

    • values

      public ShortCollection values()
      Description copied from interface: LongShortAssociativeContainer
      Returns a container view of all values present in this container. The returned collection is a view over the key set and any modifications (if allowed) introduced to the collection will propagate to the associative container immediately.
      Specified by:
      values in interface LongShortAssociativeContainer
      Returns:
      Returns a container with all values stored in this map.

    • clone

      public LongShortHashMap clone()
      Overrides:
      clone in class Object

    • toString

      public String toString()
      Convert the contents of this map to a human-friendly string.
      Overrides:
      toString in class Object

    • visualizeKeyDistribution

      public String visualizeKeyDistribution(int characters)
      Description copied from interface: LongShortMap
      Visually depict the distribution of keys.
      Specified by:
      visualizeKeyDistribution in interface LongShortMap
      Parameters:
      characters - The number of characters to "squeeze" the entire buffer into.
      Returns:
      Returns a sequence of characters where '.' depicts an empty fragment of the internal buffer and 'X' depicts full or nearly full capacity within the buffer's range and anything between 1 and 9 is between.

    • from

      public static LongShortHashMap from(long[] keys, short[] values)
      Creates a hash map from two index-aligned arrays of key-value pairs.

    • hashKey

      protected int hashKey(long key)
      Returns a hash code for the given key.

      The output from this function should evenly distribute keys across the entire integer range.

    • verifyLoadFactor

      protected double verifyLoadFactor(double loadFactor)
      Validate load factor range and return it. Override and suppress if you need insane load factors.

    • rehash

      protected void rehash(long[] fromKeys, short[] fromValues)
      Rehash from old buffers to new buffers.

    • allocateBuffers

      protected void allocateBuffers(int arraySize)
      Allocate new internal buffers. This method attempts to allocate and assign internal buffers atomically (either allocations succeed or not).

    • allocateThenInsertThenRehash

      protected void allocateThenInsertThenRehash(int slot, long pendingKey, short pendingValue)
      This method is invoked when there is a new key/ value pair to be inserted into the buffers but there is not enough empty slots to do so.

      New buffers are allocated. If this succeeds, we know we can proceed with rehashing so we assign the pending element to the previous buffer (possibly violating the invariant of having at least one empty slot) and rehash all keys, substituting new buffers at the end.

    • shiftConflictingKeys

      protected void shiftConflictingKeys(int gapSlot)
      Shift all the slot-conflicting keys and values allocated to (and including) slot.