org.limewire.collection
Class IntHashMap<V>

java.lang.Object
  org.limewire.collection.IntHashMap<V>

All Implemented Interfaces:

java.io.Serializable

public class IntHashMap<V>
extends java.lang.Object
implements java.io.Serializable

A hash map that uses primitive ints for the key rather than objects.

Note that this class is for internal optimization purposes only, and may not be supported in future releases of Jakarta Commons Lang. Utilities of this sort may be included in future releases of Jakarta Commons Collections.

Since:

2.0

See Also:

HashMap, Serialized Form

Constructor Summary

IntHashMap()
Constructs a new, empty hash table with a default capacity and load factor, which is 20 and 0.75 respectively.

IntHashMap(int initialCapacity)
Constructs a new, empty hash table with the specified initial capacity and default load factor, which is 0.75.

IntHashMap(int initialCapacity, float loadFactor)
Constructs a new, empty hash table with the specified initial capacity and the specified load factor.

IntHashMap(IntHashMap<? extends V> m)
Copy constructor.

Method Summary

void	clear() Clears this hash table so that it contains no keys.
boolean	contains(java.lang.Object value) Tests if some key maps into the specified value in this hash table.
boolean	containsKey(int key) Tests if the specified object is a key in this hash table.
boolean	containsValue(java.lang.Object value) Returns true if this HashMap maps one or more keys to this value.
V	get(int key) Returns the value to which the specified key is mapped in this map.
boolean	isEmpty() Tests if this hash table maps no keys to values.
V	put(int key, V value) Maps the specified key to the specified value in this hash table.
void	putAll(IntHashMap<? extends V> m) Adds all elements from m to this.
protected void	rehash() Increases the capacity of and internally reorganizes this hash table, in order to accommodate and access its entries more efficiently.
V	remove(int key) Removes the key (and its corresponding value) from this hash table.
int	size() Returns the number of keys in this hash table.
java.lang.String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

IntHashMap

public IntHashMap()

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

IntHashMap

public IntHashMap(int initialCapacity)

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

Parameters:

initialCapacity - the initial capacity of the hash table.

Throws:

java.lang.IllegalArgumentException - if the initial capacity is less than zero.

IntHashMap

public IntHashMap(int initialCapacity,
                  float loadFactor)

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

Parameters:

initialCapacity - the initial capacity of the hash table.

loadFactor - the load factor of the hash table.

Throws:

java.lang.IllegalArgumentException - if the initial capacity is less than zero, or if the load factor is nonpositive.

IntHashMap

public IntHashMap(IntHashMap<? extends V> m)

Copy constructor.

Parameters:

m - the IntHashMap to copy

Method Detail

putAll

public void putAll(IntHashMap<? extends V> m)

Adds all elements from m to this.

size

public int size()

Returns the number of keys in this hash table.

Returns:

the number of keys in this hash table.

isEmpty

public boolean isEmpty()

Tests if this hash table maps no keys to values.

Returns:

true if this hash table maps no keys to values; false otherwise.

contains

public boolean contains(java.lang.Object value)

Tests if some key maps into the specified value in this hash table. 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 hash table as determined by the equals method; false otherwise.

Throws:

java.lang.NullPointerException - if the value is null.

See Also:

containsKey(int), containsValue(Object), Map

containsValue

public boolean containsValue(java.lang.Object value)

Returns true if this HashMap maps one or more keys to this value.

Note that this method is identical in functionality to contains (which predates the Map interface).

Parameters:

value - value whose presence in this HashMap is to be tested.

Returns:

true/false

Since:

JDK1.2

See Also:

Map

containsKey

public boolean containsKey(int key)

Tests if the specified object is a key in this hash table.

Parameters:

key - possible key.

Returns:

true if and only if the specified object is a key in this hash table, as determined by the equals method; false otherwise.

See Also:

contains(Object)

get

public V get(int key)

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

Parameters:

key - a key in the hash table.

Returns:

the value to which the key is mapped in this hash table; null if the key is not mapped to any value in this hash table.

See Also:

put(int, Object)

rehash

protected void rehash()

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

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

put

public V put(int key,
             V value)

Maps the specified key to the specified value in this hash table. 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 hash table key.

value - the value.

Returns:

the previous value of the specified key in this hash table, or null if it did not have one.

Throws:

java.lang.NullPointerException - if the key is null.

See Also:

get(int)

remove

public V remove(int key)

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

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

Parameters:

key - the key that needs to be removed.

Returns:

the value to which the key had been mapped in this hash table, or null if the key did not have a mapping.

clear

public void clear()

Clears this hash table so that it contains no keys.

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object