org.apache.commons.collections.map
Class CaseInsensitiveMap

java.lang.Object
  |
  +--java.util.AbstractMap
        |
        +--org.apache.commons.collections.map.AbstractHashedMap
              |
              +--org.apache.commons.collections.map.CaseInsensitiveMap

All Implemented Interfaces:

Cloneable, IterableMap, Map, Serializable

public class CaseInsensitiveMap

extends AbstractHashedMap

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.toString().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: 1.4 $ $Date: 2004/02/18 01:13:19 $

Author:

Commons-Collections team

See Also:

Serialized Form

Nested Class Summary

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

AbstractHashedMap.EntrySet, AbstractHashedMap.EntrySetIterator, AbstractHashedMap.HashEntry, AbstractHashedMap.HashIterator, AbstractHashedMap.HashMapIterator, AbstractHashedMap.KeySet, AbstractHashedMap.KeySetIterator, AbstractHashedMap.Values, AbstractHashedMap.ValuesIterator

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 map)
Constructor copying elements from another map.

Method Summary

Object	clone() Clones the map without cloning the keys or values.
protected Object	convertKey(Object key) Overrides convertKey() from AbstractHashedMap to convert keys to lower case.

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, get, getEntry, hash, hashCode, hashIndex, init, isEmpty, isEqualKey, isEqualValue, keySet, mapIterator, put, putAll, 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 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 Object convertKey(Object key)

Overrides convertKey() from AbstractHashedMap to convert keys to lower case.

Returns null if key is null.

Overrides:

convertKey in class AbstractHashedMap

Parameters:

key - the key convert

Returns:

the converted key

clone

public Object clone()

Clones the map without cloning the keys or values.

Overrides:

clone in class AbstractHashedMap

Returns:

a shallow clone