org.apache.openjpa.lib.util.concurrent
Class NullSafeConcurrentHashMap

java.lang.Object
  java.util.AbstractMap<K,V>
      java.util.concurrent.ConcurrentHashMap
          org.apache.openjpa.lib.util.concurrent.NullSafeConcurrentHashMap

All Implemented Interfaces:

Serializable, ConcurrentMap, Map

Direct Known Subclasses:

SizedConcurrentHashMap

public class NullSafeConcurrentHashMap
extends ConcurrentHashMap

A subclass of ConcurrentHashMap that allows null keys and values. In exchange, it weakens the contract of putIfAbsent(java.lang.Object, java.lang.Object) and the other concurrent methods added in #ConcurrentHashMap.

Since:

1.1.0

See Also:

Serialized Form

Nested Class Summary

static interface

NullSafeConcurrentHashMap.KeyFilter

Nested classes/interfaces inherited from class java.util.AbstractMap

AbstractMap.SimpleEntry<K,V>, AbstractMap.SimpleImmutableEntry<K,V>

Nested classes/interfaces inherited from interface java.util.Map

Map.Entry<K,V>

Constructor Summary

NullSafeConcurrentHashMap()

NullSafeConcurrentHashMap(int size, float load, int concurrencyLevel)

Method Summary

boolean	contains(Object value)
boolean	containsKey(Object key)
boolean	containsValue(Object value)
Enumeration	elements()
Set	entrySet()
Object	get(Object key)
Enumeration	keys()
Set	keySet()
Object	put(Object key, Object value)
Object	putIfAbsent(Object key, Object value)
Iterator<Map.Entry>	randomEntryIterator() The returned data structure should not be shared among multiple threads.
Object	remove(Object key)
boolean	remove(Object key, Object value)
Map.Entry	removeRandom()
Object	replace(Object key, Object value)
boolean	replace(Object key, Object oldValue, Object newValue)
Collection	values()

Methods inherited from class java.util.concurrent.ConcurrentHashMap

clear, isEmpty, putAll, size

Methods inherited from class java.util.AbstractMap

clone, equals, hashCode, toString

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.util.Map

equals, hashCode

Constructor Detail

NullSafeConcurrentHashMap

public NullSafeConcurrentHashMap(int size,
                                 float load,
                                 int concurrencyLevel)

NullSafeConcurrentHashMap

public NullSafeConcurrentHashMap()

Method Detail

removeRandom

public Map.Entry removeRandom()

randomEntryIterator

public Iterator<Map.Entry> randomEntryIterator()

The returned data structure should not be shared among multiple threads.

remove

public Object remove(Object key)

Specified by:

remove in interface Map

Overrides:

remove in class ConcurrentHashMap

remove

public boolean remove(Object key,
                      Object value)

Specified by:

remove in interface ConcurrentMap

Overrides:

remove in class ConcurrentHashMap

replace

public boolean replace(Object key,
                       Object oldValue,
                       Object newValue)

Specified by:

replace in interface ConcurrentMap

Overrides:

replace in class ConcurrentHashMap

replace

public Object replace(Object key,
                      Object value)

Specified by:

replace in interface ConcurrentMap

Overrides:

replace in class ConcurrentHashMap

putIfAbsent

public Object putIfAbsent(Object key,
                          Object value)

Specified by:

putIfAbsent in interface ConcurrentMap

Overrides:

putIfAbsent in class ConcurrentHashMap

put

public Object put(Object key,
                  Object value)

Specified by:

put in interface Map

Overrides:

put in class ConcurrentHashMap

get

public Object get(Object key)

Specified by:

get in interface Map

Overrides:

get in class ConcurrentHashMap

containsKey

public boolean containsKey(Object key)

Specified by:

containsKey in interface Map

Overrides:

containsKey in class ConcurrentHashMap

containsValue

public boolean containsValue(Object value)

Specified by:

containsValue in interface Map

Overrides:

containsValue in class ConcurrentHashMap

contains

public boolean contains(Object value)

Overrides:

contains in class ConcurrentHashMap

elements

public Enumeration elements()

Overrides:

elements in class ConcurrentHashMap

entrySet

public Set entrySet()

Specified by:

entrySet in interface Map

Overrides:

entrySet in class ConcurrentHashMap

keys

public Enumeration keys()

Overrides:

keys in class ConcurrentHashMap

keySet

public Set keySet()

Specified by:

keySet in interface Map

Overrides:

keySet in class ConcurrentHashMap

values

public Collection values()

Specified by:

values in interface Map

Overrides:

values in class ConcurrentHashMap