Class IdentityObjectIntMap<K>

java.lang.Object
com.esotericsoftware.kryo.util.IdentityObjectIntMap<K>

public class IdentityObjectIntMap<K> extends Object
An unordered map where identity comparison is used for keys and the values are ints. This implementation is a cuckoo hash map using 3 hashes, random walking, and a small stash for problematic keys. Null keys are not allowed. No allocation is done except when growing the table size.

This map performs very fast get, containsKey, and remove (typically O(1), worst case O(log(n))). Put may be a bit slower, depending on hash collisions. Load factors greater than 0.91 greatly increase the chances the map will have to rehash to the next higher POT size.
  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    int
     
  • Constructor Summary

    Constructors
    Constructor
    Description
    Creates a new map with an initial capacity of 32 and a load factor of 0.8.
    IdentityObjectIntMap(int initialCapacity)
    Creates a new map with a load factor of 0.8.
    IdentityObjectIntMap(int initialCapacity, float loadFactor)
    Creates a new map with the specified initial capacity and load factor.
  • Method Summary

    Modifier and Type
    Method
    Description
    void
     
    boolean
     
    boolean
    containsValue(int value)
    Returns true if the specified value is in the map.
    void
    ensureCapacity(int additionalCapacity)
    Increases the size of the backing array to acommodate the specified number of additional items.
    findKey(int value)
    Returns the key for the specified value, or null if it is not in the map.
    int
    get(K key, int defaultValue)
     
    int
    getAndIncrement(K key, int defaultValue, int increment)
    Returns the key's current value and increments the stored value.
    void
    put(K key, int value)
     
    int
    remove(K key, int defaultValue)
     
     

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
  • Field Details

    • size

      public int size
  • Constructor Details

    • IdentityObjectIntMap

      public IdentityObjectIntMap()
      Creates a new map with an initial capacity of 32 and a load factor of 0.8. This map will hold 25 items before growing the backing table.
    • IdentityObjectIntMap

      public IdentityObjectIntMap(int initialCapacity)
      Creates a new map with a load factor of 0.8. This map will hold initialCapacity * 0.8 items before growing the backing table.
    • IdentityObjectIntMap

      public IdentityObjectIntMap(int initialCapacity, float loadFactor)
      Creates a new map with the specified initial capacity and load factor. This map will hold initialCapacity * loadFactor items before growing the backing table.
  • Method Details

    • put

      public void put(K key, int value)
    • get

      public int get(K key, int defaultValue)
      Parameters:
      defaultValue - Returned if the key was not associated with a value.
    • getAndIncrement

      public int getAndIncrement(K key, int defaultValue, int increment)
      Returns the key's current value and increments the stored value. If the key is not in the map, defaultValue + increment is put into the map.
    • remove

      public int remove(K key, int defaultValue)
    • clear

      public void clear()
    • containsValue

      public boolean containsValue(int value)
      Returns true if the specified value is in the map. Note this traverses the entire map and compares every value, which may be an expensive operation.
    • containsKey

      public boolean containsKey(K key)
    • findKey

      public K findKey(int value)
      Returns the key for the specified value, or null if it is not in the map. Note this traverses the entire map and compares every value, which may be an expensive operation.
    • ensureCapacity

      public void ensureCapacity(int additionalCapacity)
      Increases the size of the backing array to acommodate the specified number of additional items. Useful before adding many items to avoid multiple backing array resizes.
    • toString

      public String toString()
      Overrides:
      toString in class Object