pt.moredata.util
Class FullHashMap

java.lang.Object
  java.util.AbstractMap
      java.util.HashMap
          pt.moredata.util.FullHashMap

All Implemented Interfaces:

java.lang.Cloneable, java.util.Map, java.io.Serializable

public class FullHashMap

extends java.util.HashMap

FullHashMap.java Esta classe disponibiliza as funcionalidades existentes na classe HashMap e acrescenta a possibilidade de fazer o mapeamento inverso. Ou seja dado um determinado valor saber qual e a sua chave. Um objecto do tipo FullHashMap devera ocupar o dobro de um objecto HashMap. O mapeamento tem de ser de 1 para 1 ou seja, apos um put(key1, value1) nao e permitido efectuar put(key2, value1). TODO Implementar os metodos que nao estao implementados Company MoreData

Version:

$Revision: 1.1.1.1 $

Author:

pcarmo

See Also:

Serialized Form

Constructor Summary

FullHashMap()
Constructs an empty HashMap with the default initial capacity (16) and the default load factor (0.75).

FullHashMap(int initialCapacity)
Constructs an empty HashMap with the specified initial capacity and the default load factor (0.75).

FullHashMap(int initialCapacity, float loadFactor)
Constructs an empty HashMap with the specified initial capacity and load factor.

Method Summary

void	clear() Removes all mappings from this map.
java.lang.Object	clone() Returns a shallow copy of this HashMap instance: the keys and values themselves are not cloned.
boolean	containsKey(java.lang.Object key) Returns true if this map contains a mapping for the specified key.
boolean	containsValue(java.lang.Object value) Returns true if this map maps one or more keys to the specified value.
java.util.Set	entrySet() Returns a collection view of the mappings contained in this map.
boolean	equals(java.lang.Object o) Compares the specified object with this map for equality.
java.lang.Object	get(java.lang.Object key) Returns the value to which the specified key is mapped in this identity hash map, or null if the map contains no mapping for this key.
java.lang.Object	getKey(java.lang.Object value)
boolean	isEmpty() Returns true if this map contains no key-value mappings.
java.util.Set	keySet() Returns a set view of the keys contained in this map.
java.lang.Object	put(java.lang.Object key, java.lang.Object value) Associates the specified value with the specified key in this map.
void	putAll(java.util.Map t) Copies all of the mappings from the specified map to this map These mappings will replace any mappings that this map had for any of the keys currently in the specified map.
java.lang.Object	remove(java.lang.Object key) Removes the mapping for this key from this map if present.
int	size() Returns the number of key-value mappings in this map.
java.util.Collection	values() Returns a collection view of the values contained in this map.

Methods inherited from class java.util.AbstractMap

hashCode, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Map

hashCode

Constructor Detail

FullHashMap

public FullHashMap(int initialCapacity,
                   float loadFactor)

Constructs an empty HashMap with the specified initial capacity and load factor.

Parameters:

initialCapacity - The initial capacity.

loadFactor - The load factor.

Throws:

java.lang.IllegalArgumentException - if the initial capacity is negative or the load factor is nonpositive.

FullHashMap

public FullHashMap(int initialCapacity)

Constructs an empty HashMap with the specified initial capacity and the default load factor (0.75).

Parameters:

initialCapacity - the initial capacity.

Throws:

java.lang.IllegalArgumentException - if the initial capacity is negative.

FullHashMap

public FullHashMap()

Constructs an empty HashMap with the default initial capacity (16) and the default load factor (0.75).

Method Detail

clear

public void clear()

Removes all mappings from this map.

clone

public java.lang.Object clone()

Returns a shallow copy of this HashMap instance: the keys and values themselves are not cloned.

Returns:

a shallow copy of this map.

containsKey

public boolean containsKey(java.lang.Object key)

Returns true if this map contains a mapping for the specified key.

Parameters:

key - The key whose presence in this map is to be tested

Returns:

true if this map contains a mapping for the specified key.

containsValue

public boolean containsValue(java.lang.Object value)

Returns true if this map maps one or more keys to the specified value.

Parameters:

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

Returns:

true if this map maps one or more keys to the specified value.

entrySet

public java.util.Set entrySet()

Returns a collection view of the mappings contained in this map. Each element in the returned collection is a Map.Entry. The collection is backed by the map, so changes to the map are reflected in the collection, and vice-versa. The collection supports element removal, which removes the corresponding mapping from the map, via the Iterator.remove, Collection.remove, removeAll, retainAll, and clear operations. It does not support the add or addAll operations.

Returns:

a collection view of the mappings contained in this map.

See Also:

Map.Entry

equals

public boolean equals(java.lang.Object o)

Compares the specified object with this map for equality. Returns true if the given object is also a map and the two maps represent the same mappings. More formally, two maps t1 and t2 represent the same mappings if t1.keySet().equals(t2.keySet()) and for every key k in t1.keySet(), (t1.get(k)==null ? t2.get(k)==null : t1.get(k).equals(t2.get(k))) . This ensures that the equals method works properly across different implementations of the map interface.

This implementation first checks if the specified object is this map; if so it returns true. Then, it checks if the specified object is a map whose size is identical to the size of this set; if not, it it returns false. If so, it iterates over this map's entrySet collection, and checks that the specified map contains each mapping that this map contains. If the specified map fails to contain such a mapping, false is returned. If the iteration completes, true is returned.

Parameters:

o - object to be compared for equality with this map.

Returns:

true if the specified object is equal to this map.

get

public java.lang.Object get(java.lang.Object key)

Returns the value to which the specified key is mapped in this identity hash map, or null if the map contains no mapping for this key. A return value of null does not necessarily indicate that the map contains no mapping for the key; it is also possible that the map explicitly maps the key to null. The containsKey method may be used to distinguish these two cases.

Parameters:

key - the key whose associated value is to be returned.

Returns:

the value to which this map maps the specified key, or null if the map contains no mapping for this key.

See Also:

put(Object, Object)

getKey

public java.lang.Object getKey(java.lang.Object value)

isEmpty

public boolean isEmpty()

Returns true if this map contains no key-value mappings.

Returns:

true if this map contains no key-value mappings.

keySet

public java.util.Set keySet()

Returns a set view of the keys contained in this map. The set is backed by the map, so changes to the map are reflected in the set, and vice-versa. The set supports element removal, which removes the corresponding mapping from this map, via the Iterator.remove, Set.remove, removeAll, retainAll, and clear operations. It does not support the add or addAll operations.

Returns:

a set view of the keys contained in this map.

put

public java.lang.Object put(java.lang.Object key,
                            java.lang.Object value)

Associates the specified value with the specified key in this map. If the map previously contained a mapping for this key, the old value is replaced.

Parameters:

key - key with which the specified value is to be associated.

value - value to be associated with the specified key.

Returns:

previous value associated with specified key, or null if there was no mapping for key. A null return can also indicate that the HashMap previously associated null with the specified key.

Throws:

RutimeException - if value is already maped by another key.

putAll

public void putAll(java.util.Map t)

Copies all of the mappings from the specified map to this map These mappings will replace any mappings that this map had for any of the keys currently in the specified map.

Parameters:

t - mappings to be stored in this map.

Throws:

java.lang.NullPointerException - if the specified map is null.

remove

public java.lang.Object remove(java.lang.Object key)

Removes the mapping for this key from this map if present.

Parameters:

key - key whose mapping is to be removed from the map.

Returns:

previous value associated with specified key, or null if there was no mapping for key. A null return can also indicate that the map previously associated null with the specified key.

size

public int size()

Returns the number of key-value mappings in this map.

Returns:

the number of key-value mappings in this map.

values

public java.util.Collection values()

Returns a collection view of the values contained in this map. The collection is backed by the map, so changes to the map are reflected in the collection, and vice-versa. The collection supports element removal, which removes the corresponding mapping from this map, via the Iterator.remove, Collection.remove, removeAll, retainAll, and clear operations. It does not support the add or addAll operations.

Returns:

a collection view of the values contained in this map.