Class CaseInsensitiveMap<K,V>
- All Implemented Interfaces:
Serializable
,Cloneable
,Map<K,
,V> Get<K,
,V> IterableGet<K,
,V> IterableMap<K,
,V> Put<K,
V>
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<String, String> map = new CaseInsensitiveMap<String, String>();
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}.
This map will violate the detail of various Map and map view contracts.
As a general rule, don't compare this map to other maps. In particular, you can't
use decorators like
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 ListOrderedMap
on it, which silently assume that these
contracts are fulfilled.
Collections.synchronizedMap(Map)
. This class may throw
exceptions when accessed by concurrent threads without synchronization.
- Since:
- 3.0
- Version:
- $Id: CaseInsensitiveMap.java 1533984 2013-10-20 21:12:51Z tn $
- See Also:
-
Nested Class Summary
Nested classes/interfaces inherited from class org.apache.commons.collections4.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>, AbstractHashedMap.KeySetIterator<K>, AbstractHashedMap.Values<V>, AbstractHashedMap.ValuesIterator<V> Nested classes/interfaces inherited from class java.util.AbstractMap
AbstractMap.SimpleEntry<K extends Object,
V extends Object>, AbstractMap.SimpleImmutableEntry<K extends Object, V extends Object> -
Field Summary
Fields inherited from class org.apache.commons.collections4.map.AbstractHashedMap
DEFAULT_CAPACITY, DEFAULT_LOAD_FACTOR, DEFAULT_THRESHOLD, GETKEY_INVALID, GETVALUE_INVALID, MAXIMUM_CAPACITY, NO_NEXT_ENTRY, NO_PREVIOUS_ENTRY, NULL, REMOVE_INVALID, SETVALUE_INVALID
-
Constructor Summary
ConstructorsConstructorDescriptionConstructs 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 K, ? extends V> map) Constructor copying elements from another map. -
Method Summary
Modifier and TypeMethodDescriptionclone()
Clones the map without cloning the keys or values.protected Object
convertKey
(Object key) Overrides convertKey() fromAbstractHashedMap
to convert keys to lower case.Methods inherited from class org.apache.commons.collections4.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
Methods inherited from interface java.util.Map
compute, computeIfAbsent, computeIfPresent, forEach, getOrDefault, merge, putIfAbsent, remove, replace, replace, replaceAll
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Constructor Details
-
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 negative
-
CaseInsensitiveMap
public CaseInsensitiveMap(int initialCapacity, float loadFactor) Constructs a new, empty map with the specified initial capacity and load factor.- Parameters:
initialCapacity
- the initial capacityloadFactor
- the load factor- Throws:
IllegalArgumentException
- if the initial capacity is negativeIllegalArgumentException
- if the load factor is less than zero
-
CaseInsensitiveMap
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 Details
-
convertKey
Overrides convertKey() fromAbstractHashedMap
to convert keys to lower case.Returns
AbstractHashedMap.NULL
if key is null.- Overrides:
convertKey
in classAbstractHashedMap<K,
V> - Parameters:
key
- the key convert- Returns:
- the converted key
-
clone
Clones the map without cloning the keys or values.- Overrides:
clone
in classAbstractHashedMap<K,
V> - Returns:
- a shallow clone
-