Package org.graph4j.util

Class IntHashMap

java.lang.Object
org.graph4j.util.IntHashMap
public class IntHashMap extends Object
Adapted after the implementation of IntHashMap in Apache Commons Collection.
Author:
Justin Couch, Alex Chaffee (alex@apache.org), Stephen Colebourne, Cristian Frăsinaru

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    static final int
    NONE
     

  • Constructor Summary

    Constructors
    Constructor
    Description
    IntHashMap()
    Constructs a new, empty hashtable with a default capacity and load factor, which is 20 and 0.75 respectively.
    IntHashMap(int initialCapacity)
    Constructs a new, empty hashtable with the specified initial capacity and default load factor, which is 0.75.
    IntHashMap(int initialCapacity, float loadFactor)
    Constructs a new, empty hashtable with the specified initial capacity and the specified load factor.
    IntHashMap(IntHashMap other)
    Copy constructor.

  • Method Summary

    Modifier and Type
    Method
    Description
    void
    clear()
    Clears this hashtable so that it contains no keys.
    boolean
    containsKey(int key)
    Tests if the specified object is a key in this hashtable.
    boolean
    containsValue(int value)
    Tests if some key maps into the specified value in this hashtable.
    int
    get(int key)
    Returns the value to which the specified key is mapped in this map.
    int
    getOrDefault(int key, int defaultValue)
     
    boolean
    isEmpty()
    Tests if this hashtable maps no keys to values.
    int[]
    keys()
     
    final int
    put(int key, int value)
    Maps the specified key to the specified value in this hashtable.
    protected void
    rehash()
    Increases the capacity of and internally reorganizes this hashtable, in order to accommodate and access its entries more efficiently.
    int
    remove(int key)
    Removes the key (and its corresponding value) from this hashtable.
    int
    size()
    Returns the number of keys in this hashtable.
    String
    toString()
     
    int[]
    values()
     

    Methods inherited from class java.lang.Object

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

  • Field Details

  • Constructor Details

    • IntHashMap

      public IntHashMap()

      Constructs a new, empty hashtable with a default capacity and load factor, which is 20 and 0.75 respectively.

    • IntHashMap

      public IntHashMap(int initialCapacity)

      Constructs a new, empty hashtable with the specified initial capacity and default load factor, which is 0.75.

      Parameters:
      initialCapacity - the initial capacity of the hashtable.
      Throws:
      IllegalArgumentException - if the initial capacity is less than zero.

    • IntHashMap

      public IntHashMap(int initialCapacity, float loadFactor)

      Constructs a new, empty hashtable with the specified initial capacity and the specified load factor.

      Parameters:
      initialCapacity - the initial capacity of the hashtable.
      loadFactor - the load factor of the hashtable.
      Throws:
      IllegalArgumentException - if the initial capacity is less than zero, or if the load factor is nonpositive.

    • IntHashMap

      public IntHashMap(IntHashMap other)
      Copy constructor.
      Parameters:
      other - the IntHashMap object that will be copied.

  • Method Details

    • size

      public int size()

      Returns the number of keys in this hashtable.

      Returns:
      the number of keys in this hashtable.

    • isEmpty

      public boolean isEmpty()

      Tests if this hashtable maps no keys to values.

      Returns:
      true if this hashtable maps no keys to values; false otherwise.

    • containsValue

      public boolean containsValue(int value)

      Tests if some key maps into the specified value in this hashtable. This operation is more expensive than the containsKey method.

      Note that this method is identical in functionality to containsValue, (which is part of the Map interface in the collections framework).

      Parameters:
      value - a value to search for.
      Returns:
      true if and only if some key maps to the value argument in this hashtable as determined by the equals method; false otherwise.
      Throws:
      NullPointerException - if the value is null.

    • containsKey

      public boolean containsKey(int key)

      Tests if the specified object is a key in this hashtable.

      Parameters:
      key - possible key.
      Returns:
      true if and only if the specified object is a key in this hashtable, as determined by the equals method; false otherwise.

    • get

      public int get(int key)

      Returns the value to which the specified key is mapped in this map.

      Parameters:
      key - a key in the hashtable.
      Returns:
      the value to which the key is mapped in this hashtable; null if the key is not mapped to any value in this hashtable.

    • getOrDefault

      public int getOrDefault(int key, int defaultValue)
      Parameters:
      key - a key.
      defaultValue - the returned value if the key is not in the hashtable.
      Returns:
      the value to which the key is mapped in this hashtable, or the default value if the key is not in the hashtable.

    • rehash

      protected void rehash()

      Increases the capacity of and internally reorganizes this hashtable, in order to accommodate and access its entries more efficiently.

      This method is called automatically when the number of keys in the hashtable exceeds this hashtable's capacity and load factor.

    • put

      public final int put(int key, int value)

      Maps the specified key to the specified value in this hashtable. The key cannot be null.

      The value can be retrieved by calling the get method with a key that is equal to the original key.

      Parameters:
      key - the hashtable key.
      value - the value.
      Returns:
      the previous value of the specified key in this hashtable, or null if it did not have one.
      Throws:
      NullPointerException - if the key is null.

    • remove

      public int remove(int key)

      Removes the key (and its corresponding value) from this hashtable.

      This method does nothing if the key is not present in the hashtable.

      Parameters:
      key - the key that needs to be removed.
      Returns:
      the value to which the key had been mapped in this hashtable, or null if the key did not have a mapping.

    • clear

      public void clear()

      Clears this hashtable so that it contains no keys.

    • keys

      public int[] keys()
      Returns:
      the keys in the hash table.

    • values

      public int[] values()
      Returns:
      the values in the hash table.

    • toString

      public String toString()
      Overrides:
      toString in class Object