|
||||||||||
PREV CLASS NEXT CLASS | FRAMES NO FRAMES | |||||||||
SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD |
A Map
providing additional atomic
putIfAbsent, remove, and replace methods.
This interface is a member of the Java Collections Framework.
Method Summary | |
java.lang.Object |
putIfAbsent(java.lang.Object key,
java.lang.Object value)
If the specified key is not already associated with a value, associate it with the given value. |
boolean |
remove(java.lang.Object key,
java.lang.Object value)
Remove entry for key only if currently mapped to given value. |
java.lang.Object |
replace(java.lang.Object key,
java.lang.Object value)
Replace entry for key only if currently mapped to some value. |
boolean |
replace(java.lang.Object key,
java.lang.Object oldValue,
java.lang.Object newValue)
Replace entry for key only if currently mapped to given value. |
Methods inherited from interface java.util.Map |
clear, containsKey, containsValue, entrySet, equals, get, hashCode, isEmpty, keySet, put, putAll, remove, size, values |
Method Detail |
public java.lang.Object putIfAbsent(java.lang.Object key, java.lang.Object value)
if (!map.containsKey(key)) return map.put(key, value); else return map.get(key);Except that the action is performed atomically.
key
- key with which the specified value is to be associated.value
- value to be associated with the specified key.
java.lang.UnsupportedOperationException
- if the put operation is
not supported by this map.
java.lang.ClassCastException
- if the class of the specified key or value
prevents it from being stored in this map.
java.lang.IllegalArgumentException
- if some aspect of this key or value
prevents it from being stored in this map.
java.lang.NullPointerException
- if this map does not permit null
keys or values, and the specified key or value is
null.public boolean remove(java.lang.Object key, java.lang.Object value)
if ((map.containsKey(key) && map.get(key).equals(value)) { map.remove(key); return true; } else return false;except that the action is performed atomically.
key
- key with which the specified value is associated.value
- value associated with the specified key.
java.lang.UnsupportedOperationException
- if the remove operation is
not supported by this map.
java.lang.NullPointerException
- if this map does not permit null
keys or values, and the specified key or value is
null.public boolean replace(java.lang.Object key, java.lang.Object oldValue, java.lang.Object newValue)
if ((map.containsKey(key) && map.get(key).equals(oldValue)) { map.put(key, newValue); return true; } else return false;except that the action is performed atomically.
key
- key with which the specified value is associated.oldValue
- value expected to be associated with the specified key.newValue
- value to be associated with the specified key.
java.lang.UnsupportedOperationException
- if the put operation is
not supported by this map.
java.lang.NullPointerException
- if this map does not permit null
keys or values, and the specified key or value is
null.public java.lang.Object replace(java.lang.Object key, java.lang.Object value)
if ((map.containsKey(key)) { return map.put(key, value); } else return null;except that the action is performed atomically.
key
- key with which the specified value is associated.value
- value to be associated with the specified key.
java.lang.UnsupportedOperationException
- if the put operation is
not supported by this map.
java.lang.NullPointerException
- if this map does not permit null
keys or values, and the specified key or value is
null.
|
||||||||||
PREV CLASS NEXT CLASS | FRAMES NO FRAMES | |||||||||
SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD |