public class CaseInsensitiveMap extends AbstractHashedMap implements Serializable, Cloneable
Map
.
Before keys are added to the map or compared to other existing keys, they are converted to all lowercase in a locale-independent fashion by using information from the Unicode data file.
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}.
Note that CaseInsensitiveMap is not synchronized and is not thread-safe.
If you wish to use this map from multiple threads concurrently, you must use
appropriate synchronization. The simplest approach is to wrap this map
using Collections.synchronizedMap(Map)
. This class may throw
exceptions when accessed by concurrent threads without synchronization.
AbstractHashedMap.EntrySet, AbstractHashedMap.EntrySetIterator, AbstractHashedMap.HashEntry, AbstractHashedMap.HashIterator, AbstractHashedMap.HashMapIterator, AbstractHashedMap.KeySet, AbstractHashedMap.KeySetIterator, AbstractHashedMap.Values, AbstractHashedMap.ValuesIterator
AbstractMap.SimpleEntry, AbstractMap.SimpleImmutableEntry
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 and Description |
---|
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.
|
Modifier and Type | Method and Description |
---|---|
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. |
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
public CaseInsensitiveMap()
public CaseInsensitiveMap(int initialCapacity)
initialCapacity
- the initial capacityIllegalArgumentException
- if the initial capacity is less than onepublic CaseInsensitiveMap(int initialCapacity, float loadFactor)
initialCapacity
- the initial capacityloadFactor
- the load factorIllegalArgumentException
- if the initial capacity is less than oneIllegalArgumentException
- if the load factor is less than zeropublic CaseInsensitiveMap(Map 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).
map
- the map to copyNullPointerException
- if the map is nullprotected Object convertKey(Object key)
AbstractHashedMap
to convert keys to
lower case.
Returns AbstractHashedMap.NULL
if key is null.
convertKey
in class AbstractHashedMap
key
- the key convertpublic Object clone()
clone
in class AbstractHashedMap
Copyright © 2001–2015 The Apache Software Foundation. All rights reserved.