org.apache.commons.transaction.memory
Class PessimisticTxMap<K,V>

java.lang.Object
  org.apache.commons.transaction.AbstractTransactionalResourceManager<BasicTxMap.MapTxContext>
      org.apache.commons.transaction.memory.BasicTxMap<K,V>
          org.apache.commons.transaction.memory.PessimisticTxMap<K,V>

All Implemented Interfaces:

Map<K,V>, ManageableResourceManager, TxMap<K,V>, TransactionalResourceManager

public class PessimisticTxMap<K,V>
extends BasicTxMap<K,V>
implements TxMap<K,V>

Map featuring transactional control.

By using pessimistic transaction control (blocking locks) this wrapper has better isolation than BasicTxMap, but also has less possible concurrency and may even deadlock. A commit, however, will never fail.

Caution:Some operations that would require global locks (e.g. size() or clear() or not properly isolated as this implementation does not support global locks.

This implementation wraps a map of type ConcurrentHashMap.

This implementation is thread-safe.

See Also:

BasicTxMap, OptimisticTxMap, ConcurrentHashMap

Nested Class Summary

class

PessimisticTxMap.LockingTxContext

Nested classes/interfaces inherited from class org.apache.commons.transaction.memory.BasicTxMap

BasicTxMap.HashEntry, BasicTxMap.MapTxContext

Nested classes/interfaces inherited from class org.apache.commons.transaction.AbstractTransactionalResourceManager

AbstractTransactionalResourceManager.AbstractTxContext

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

Map.Entry<K,V>

Field Summary

Fields inherited from class org.apache.commons.transaction.memory.BasicTxMap

wrapped

Fields inherited from class org.apache.commons.transaction.AbstractTransactionalResourceManager

activeTx

Constructor Summary

PessimisticTxMap(String name)

PessimisticTxMap(String name, LockManager<Object,Object> lm)

Method Summary

protected void	assureWriteLock(Object key)
boolean	commitCanFail() Checks whether a tried commit could possibly fail because of logical reasons.
protected PessimisticTxMap.LockingTxContext	createContext()
Set	entrySet()
Set	keySet()
V	put(K key, V value)
V	remove(Object key)
Collection	values()

Methods inherited from class org.apache.commons.transaction.memory.BasicTxMap

clear, containsKey, containsValue, get, getActiveTx, getWrappedMap, isEmpty, putAll, size

Methods inherited from class org.apache.commons.transaction.AbstractTransactionalResourceManager

commitTransaction, forgetTransaction, getCheckedActiveTx, getLm, getName, isPartofComplexTransaction, isReadOnly, isRollbackOnly, joinTransaction, prepareTransaction, rollbackTransaction, setActiveTx, setLm, setName, startTransaction

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.apache.commons.transaction.memory.TxMap

getWrappedMap

Methods inherited from interface java.util.Map

clear, containsKey, containsValue, equals, get, hashCode, isEmpty, putAll, size

Methods inherited from interface org.apache.commons.transaction.ManageableResourceManager

forgetTransaction, isReadOnly, isRollbackOnly, joinTransaction, prepareTransaction

Methods inherited from interface org.apache.commons.transaction.TransactionalResourceManager

commitTransaction, rollbackTransaction, startTransaction

Constructor Detail

PessimisticTxMap

public PessimisticTxMap(String name)

PessimisticTxMap

public PessimisticTxMap(String name,
                        LockManager<Object,Object> lm)

Method Detail

values

public Collection values()

Specified by:

values in interface Map<K,V>

Overrides:

values in class BasicTxMap<K,V>

See Also:

Map.values()

entrySet

public Set entrySet()

Specified by:

entrySet in interface Map<K,V>

Overrides:

entrySet in class BasicTxMap<K,V>

See Also:

Map.entrySet()

keySet

public Set keySet()

Specified by:

keySet in interface Map<K,V>

Overrides:

keySet in class BasicTxMap<K,V>

See Also:

Map.keySet()

remove

public V remove(Object key)

Specified by:

remove in interface Map<K,V>

Overrides:

remove in class BasicTxMap<K,V>

See Also:

Map.remove(java.lang.Object)

put

public V put(K key,
             V value)

Specified by:

put in interface Map<K,V>

Overrides:

put in class BasicTxMap<K,V>

See Also:

Map.put(java.lang.Object, java.lang.Object)

assureWriteLock

protected void assureWriteLock(Object key)

createContext

protected PessimisticTxMap.LockingTxContext createContext()

Overrides:

createContext in class BasicTxMap<K,V>

commitCanFail

public boolean commitCanFail()

Description copied from interface: ManageableResourceManager

Checks whether a tried commit could possibly fail because of logical reasons.

Specified by:

commitCanFail in interface ManageableResourceManager

Overrides:

commitCanFail in class BasicTxMap<K,V>

Returns:

true if a commit could fail