org.cojen.util
Class WeakIdentityMap
java.lang.Object
java.util.AbstractMap
org.cojen.util.WeakIdentityMap
- All Implemented Interfaces:
- Cloneable, Map
public class WeakIdentityMap
- extends AbstractMap
- implements Map, Cloneable
WeakIdentityMap is like WeakHashMap, except it uses a key's identity
hashcode and equals methods. WeakIdentityMap is not thread-safe and must be
wrapped with Collections.synchronizedMap to be made thread-safe.
The documentation for WeakHashMap states that it is intended primarily for
use with key objects whose equals methods test for object identity using the
== operator. Because WeakIdentityMap strictly follows this behavior, it is
better suited for this purpose.
Note: Weakly referenced entries may be automatically removed during
either accessor or mutator operations, possibly causing a concurrent
modification to be detected. Therefore, even if multiple threads are only
accessing this map, be sure to synchronize this map first. Also, do not
rely on the value returned by size() when using an iterator from this map.
The iterators may return less entries than the amount reported by size().
- Author:
- Brian S O'Neill
WeakIdentityMap
public WeakIdentityMap(int initialCapacity,
float loadFactor)
WeakIdentityMap
public WeakIdentityMap(int initialCapacity)
WeakIdentityMap
public WeakIdentityMap()
WeakIdentityMap
public WeakIdentityMap(Map t)
size
public int size()
- Specified by:
size
in interface Map
- Overrides:
size
in class AbstractMap
isEmpty
public boolean isEmpty()
- Specified by:
isEmpty
in interface Map
- Overrides:
isEmpty
in class AbstractMap
containsValue
public boolean containsValue(Object value)
- Specified by:
containsValue
in interface Map
- Overrides:
containsValue
in class AbstractMap
containsKey
public boolean containsKey(Object key)
- Specified by:
containsKey
in interface Map
- Overrides:
containsKey
in class AbstractMap
get
public Object get(Object key)
- Specified by:
get
in interface Map
- Overrides:
get
in class AbstractMap
put
public Object put(Object key,
Object value)
- Specified by:
put
in interface Map
- Overrides:
put
in class AbstractMap
remove
public Object remove(Object key)
- Specified by:
remove
in interface Map
- Overrides:
remove
in class AbstractMap
putAll
public void putAll(Map t)
- Specified by:
putAll
in interface Map
- Overrides:
putAll
in class AbstractMap
clear
public void clear()
- Specified by:
clear
in interface Map
- Overrides:
clear
in class AbstractMap
clone
public Object clone()
- Overrides:
clone
in class AbstractMap
keySet
public Set keySet()
- Specified by:
keySet
in interface Map
- Overrides:
keySet
in class AbstractMap
values
public Collection values()
- Specified by:
values
in interface Map
- Overrides:
values
in class AbstractMap
entrySet
public Set entrySet()
- Specified by:
entrySet
in interface Map
- Specified by:
entrySet
in class AbstractMap
toString
public String toString()
- Gets the map as a String.
- Overrides:
toString
in class AbstractMap
- Returns:
- a string version of the map
Copyright © 2004-2011 Brian S O'Neill. All Rights Reserved.