org.apache.commons.collections.map
Class CaseInsensitiveMap<V>

java.lang.Object
  java.util.AbstractMap<K,V>
      org.apache.commons.collections.map.AbstractHashedMap<String,V>
          org.apache.commons.collections.map.CaseInsensitiveMap<V>

All Implemented Interfaces:

Serializable, Cloneable, Map<String,V>, IterableMap<String,V>

public class CaseInsensitiveMap<V>
extends AbstractHashedMap<String,V>
implements Serializable, Cloneable

A case-insensitive Map.

As entries are added to the map, keys are converted to all lowercase. A new key is compared to existing keys by comparing newKey.toLower() to the lowercase values in the current KeySet.

Null keys are supported.

The keySet() method returns all lowercase keys, or nulls.

Example:

  Map map = new CaseInsensitiveMap();
  map.put("One", "One");
  map.put("Two", "Two");
  map.put(null, "Three");
  map.put("one", "Four");
 

creates a CaseInsensitiveMap with three entries.
map.get(null) returns "Three" and map.get("ONE") returns "Four". The Set returned by keySet() equals {"one", "two", null}.

Since:

Commons Collections 3.0

Version:

$Revision: 1.1.1.1 $ $Date: 2005/05/23 04:35:45 $

Author:

Matt Hall, John Watkinson, Commons-Collections team

See Also:

Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.commons.collections.map.AbstractHashedMap

AbstractHashedMap.EntrySet<K,V>, AbstractHashedMap.EntrySetIterator<K,V>, AbstractHashedMap.HashEntry<K,V>, AbstractHashedMap.HashIterator<K,V>, AbstractHashedMap.HashMapIterator<K,V>, AbstractHashedMap.KeySet<K,V>, AbstractHashedMap.KeySetIterator<K,V>, AbstractHashedMap.Values<K,V>, AbstractHashedMap.ValuesIterator<K,V>

Nested classes/interfaces inherited from interface java.util.Map

Map.Entry<K,V>

Field Summary

Fields inherited from class org.apache.commons.collections.map.AbstractHashedMap

data, DEFAULT_CAPACITY, DEFAULT_LOAD_FACTOR, DEFAULT_THRESHOLD, entrySet, GETKEY_INVALID, GETVALUE_INVALID, keySet, loadFactor, MAXIMUM_CAPACITY, modCount, NO_NEXT_ENTRY, NO_PREVIOUS_ENTRY, NULL, REMOVE_INVALID, SETVALUE_INVALID, size, threshold, values

Constructor Summary

CaseInsensitiveMap()
Constructs a new empty map with default size and load factor.

CaseInsensitiveMap(int initialCapacity)
Constructs a new, empty map with the specified initial capacity.

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

CaseInsensitiveMap(Map<? extends String,? extends V> map)
Constructor copying elements from another map.

Method Summary

Object	clone() Clones the map without cloning the keys or values.
protected String	convertKey(String key) Converts keys to lower case.
V	get(Object key) Gets the value mapped to the key specified.
V	put(String s, V v) Puts a key-value mapping into this map.
void	putAll(Map<? extends String,? extends V> map) Puts all the values from the specified map into this map.

Methods inherited from class org.apache.commons.collections.map.AbstractHashedMap

addEntry, addMapping, calculateNewCapacity, calculateThreshold, checkCapacity, clear, containsKey, containsValue, createEntry, createEntrySetIterator, createKeySetIterator, createValuesIterator, destroyEntry, doReadObject, doWriteObject, ensureCapacity, entryHashCode, entryKey, entryNext, entrySet, entryValue, equals, getEntry, hash, hashCode, hashIndex, init, isEmpty, isEqualKey, isEqualValue, keySet, mapIterator, remove, removeEntry, removeMapping, reuseEntry, size, toString, updateEntry, values

Methods inherited from class java.lang.Object

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

Constructor Detail

CaseInsensitiveMap

public CaseInsensitiveMap()

Constructs a new empty map with default size and load factor.

CaseInsensitiveMap

public CaseInsensitiveMap(int initialCapacity)

Constructs a new, empty map with the specified initial capacity.

Parameters:

initialCapacity - the initial capacity

Throws:

IllegalArgumentException - if the initial capacity is less than one

CaseInsensitiveMap

public CaseInsensitiveMap(int initialCapacity,
                          float loadFactor)

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

Parameters:

initialCapacity - the initial capacity

loadFactor - the load factor

Throws:

IllegalArgumentException - if the initial capacity is less than one

IllegalArgumentException - if the load factor is less than zero

CaseInsensitiveMap

public CaseInsensitiveMap(Map<? extends String,? extends V> map)

Constructor copying elements from another map.

Keys will be converted to lower case strings, which may cause some entries to be removed (if string representation of keys differ only by character case).

Parameters:

map - the map to copy

Throws:

NullPointerException - if the map is null

Method Detail

convertKey

protected String convertKey(String key)

Converts keys to lower case.

Returns null if key is null.

Parameters:

key - the key convert

Returns:

the converted key

get

public V get(Object key)

Description copied from class: AbstractHashedMap

Gets the value mapped to the key specified.

Specified by:

get in interface Map<String,V>

Overrides:

get in class AbstractHashedMap<String,V>

Parameters:

key - the key

Returns:

the mapped value, null if no match

put

public V put(String s,
             V v)

Description copied from class: AbstractHashedMap

Puts a key-value mapping into this map.

Specified by:

put in interface Map<String,V>

Overrides:

put in class AbstractHashedMap<String,V>

Parameters:

s - the key to add

v - the value to add

Returns:

the value previously mapped to this key, null if none

putAll

public void putAll(Map<? extends String,? extends V> map)

Description copied from class: AbstractHashedMap

Puts all the values from the specified map into this map.

This implementation iterates around the specified map and uses AbstractHashedMap.put(Object, Object).

Specified by:

putAll in interface Map<String,V>

Overrides:

putAll in class AbstractHashedMap<String,V>

Parameters:

map - the map to add

clone

public Object clone()

Clones the map without cloning the keys or values.

Overrides:

clone in class AbstractHashedMap<String,V>

Returns:

a shallow clone