net.sf.ehcache.transaction.xa
Class EhcacheXAStoreImpl

java.lang.Object
  net.sf.ehcache.transaction.xa.EhcacheXAStoreImpl

All Implemented Interfaces:

EhcacheXAStore

public class EhcacheXAStoreImpl
extends java.lang.Object
implements EhcacheXAStore

Default implementation of EhcacheXAStore.

It uses ConcurrentHashMap for the local data (non safe in case of failure) and requires a "safe" Store for the oldVersionStore, and a reference to the underlying Store.

Author:

Alex Snaps

Nested Class Summary

static class	EhcacheXAStoreImpl.Version Represents an Element's version for a Store
static class	EhcacheXAStoreImpl.VersionTable A table containing element version information

Field Summary

protected Store	oldVersionStore protected for testing
protected java.util.concurrent.ConcurrentMap<javax.transaction.xa.Xid,PreparedContext>	prepareXids protected for testing
protected java.util.concurrent.ConcurrentMap<javax.transaction.xa.Xid,XATransactionContext>	transactionContextXids protected for testing
protected Store	underlyingStore protected for testing
protected EhcacheXAStoreImpl.VersionTable	versionTable protected for testing

Constructor Summary

EhcacheXAStoreImpl(Store underlyingStore, Store oldVersionStore)
Constructor

Method Summary

void	checkin(java.lang.Object key, javax.transaction.xa.Xid xid, boolean readOnly) Checks in changes to a key
long	checkout(java.lang.Object key, javax.transaction.xa.Xid xid) Checks a version for en Element out of the store
PreparedContext	createPreparedContext() Return a newly created prepare context if none exist.
TransactionContext	createTransactionContext(javax.transaction.xa.Xid xid) Creates a new TransactionContext for a given Transaction
Store	getOldVersionStore() Getter to the guarding read-only oldVersionStore
PreparedContext	getPreparedContext(javax.transaction.xa.Xid xid) Gets a PreparedContext from a persistent store for a previously prepared Transaction
javax.transaction.xa.Xid[]	getPreparedXids() Lists prepared, yet not commited Xids
TransactionContext	getTransactionContext(javax.transaction.xa.Xid xid) Gets a stored TransactionContext for a given Transaction
Store	getUnderlyingStore() Getter to the underlying store
boolean	isPrepared(javax.transaction.xa.Xid xid) Checks whether a Transaction is prepared
boolean	isValid(VersionAwareCommand command, javax.transaction.xa.Xid xid) Checks whether a command can safely be executed against the store, depending on the version lock
void	prepare(javax.transaction.xa.Xid xid, PreparedContext context) Save the Transaction's data as being prepared
void	removeData(javax.transaction.xa.Xid xid) Removes stored data of a given Xid

Methods inherited from class java.lang.Object

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

Field Detail

transactionContextXids

protected final java.util.concurrent.ConcurrentMap<javax.transaction.xa.Xid,XATransactionContext> transactionContextXids

protected for testing

prepareXids

protected final java.util.concurrent.ConcurrentMap<javax.transaction.xa.Xid,PreparedContext> prepareXids

protected for testing

versionTable

protected final EhcacheXAStoreImpl.VersionTable versionTable

protected for testing

underlyingStore

protected Store underlyingStore

protected for testing

oldVersionStore

protected Store oldVersionStore

protected for testing

Constructor Detail

EhcacheXAStoreImpl

public EhcacheXAStoreImpl(Store underlyingStore,
                          Store oldVersionStore)

Constructor

Parameters:

underlyingStore - the real underlying store

oldVersionStore - the old version, read-only, used to access keys during 2pc

Method Detail

getOldVersionStore

public Store getOldVersionStore()

Getter to the guarding read-only oldVersionStore

Specified by:

getOldVersionStore in interface EhcacheXAStore

Returns:

the oldVersionStore

isPrepared

public boolean isPrepared(javax.transaction.xa.Xid xid)

Checks whether a Transaction is prepared

Specified by:

isPrepared in interface EhcacheXAStore

Parameters:

xid - the Xid of the Transaction

Returns:

true if prepared

removeData

public void removeData(javax.transaction.xa.Xid xid)

Removes stored data of a given Xid

Specified by:

removeData in interface EhcacheXAStore

Parameters:

xid - the Xid of the Transaction

checkin

public void checkin(java.lang.Object key,
                    javax.transaction.xa.Xid xid,
                    boolean readOnly)

Checks in changes to a key

Specified by:

checkin in interface EhcacheXAStore

Parameters:

key - the key of the affected Element in the Store

xid - the Xid of the Transaction executing the change

readOnly - whether the command modified the underlying Store

checkout

public long checkout(java.lang.Object key,
                     javax.transaction.xa.Xid xid)

Checks a version for en Element out of the store

Specified by:

checkout in interface EhcacheXAStore

Parameters:

key - the key to the Element in the store

xid - the Xid of the Transaction reading

Returns:

the version of the element

createTransactionContext

public TransactionContext createTransactionContext(javax.transaction.xa.Xid xid)

Creates a new TransactionContext for a given Transaction

Specified by:

createTransactionContext in interface EhcacheXAStore

Parameters:

xid - of current transaction

Returns:

a TransactionContext for that Transaction

getPreparedXids

public javax.transaction.xa.Xid[] getPreparedXids()

Lists prepared, yet not commited Xids

Specified by:

getPreparedXids in interface EhcacheXAStore

Returns:

array of uncommited, yet prepared xids

getTransactionContext

public TransactionContext getTransactionContext(javax.transaction.xa.Xid xid)

Gets a stored TransactionContext for a given Transaction

Specified by:

getTransactionContext in interface EhcacheXAStore

Parameters:

xid - The Xid of the Transaction

Returns:

the matching TransactionContext

isValid

public boolean isValid(VersionAwareCommand command,
                       javax.transaction.xa.Xid xid)

Checks whether a command can safely be executed against the store, depending on the version lock

Specified by:

isValid in interface EhcacheXAStore

Parameters:

command - the Command

Returns:

true if safe, false if cannot be applied anymore

prepare

public void prepare(javax.transaction.xa.Xid xid,
                    PreparedContext context)

Save the Transaction's data as being prepared

Specified by:

prepare in interface EhcacheXAStore

Parameters:

xid - the Xid of the Transaction

context - the context with the transaction data

getPreparedContext

public PreparedContext getPreparedContext(javax.transaction.xa.Xid xid)

Gets a PreparedContext from a persistent store for a previously prepared Transaction

Specified by:

getPreparedContext in interface EhcacheXAStore

Parameters:

xid - The Xid of the Transaction

Returns:

the Prepared context for the Transaction, or null

createPreparedContext

public PreparedContext createPreparedContext()

Return a newly created prepare context if none exist.

Specified by:

createPreparedContext in interface EhcacheXAStore

Returns:

a new PreparedContext

getUnderlyingStore

public Store getUnderlyingStore()

Getter to the underlying store

Specified by:

getUnderlyingStore in interface EhcacheXAStore

Returns:

the store