/**
* Copyright (C) 2000-2010 Atomikos <info@atomikos.com>
*
* This code ("Atomikos TransactionsEssentials"), by itself,
* is being distributed under the
* Apache License, Version 2.0 ("License"), a copy of which may be found at
* http://www.atomikos.com/licenses/apache-license-2.0.txt .
* You may not use this file except in compliance with the License.
*
* While the License grants certain patent license rights,
* those patent license rights only extend to the use of
* Atomikos TransactionsEssentials by itself.
*
* This code (Atomikos TransactionsEssentials) contains certain interfaces
* in package (namespace) com.atomikos.icatch
* (including com.atomikos.icatch.Participant) which, if implemented, may
* infringe one or more patents held by Atomikos.
* It should be appreciated that you may NOT implement such interfaces;
* licensing to implement these interfaces must be obtained separately from Atomikos.
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
*/
package com.atomikos.persistence.imp;
import java.util.Enumeration;
import java.util.Vector;
import com.atomikos.finitestates.FSMEnterEvent;
import com.atomikos.finitestates.FSMPreEnterListener;
import com.atomikos.persistence.LogException;
import com.atomikos.persistence.ObjectImage;
import com.atomikos.persistence.ObjectLog;
import com.atomikos.persistence.StateRecoverable;
import com.atomikos.persistence.StateRecoveryManager;
/**
*
*
* A standard implementation of a state recovery manager.
*/
public class StateRecoveryManagerImp implements StateRecoveryManager,
FSMPreEnterListener
{
protected ObjectLog objectlog_;
// for delegation of storage tasks
/**
* Construct a new instance that uses an underlying log.
*
* @param objectlog
* The log to delegate to.
*/
public StateRecoveryManagerImp ( ObjectLog objectlog )
{
objectlog_ = objectlog;
}
/**
* @see StateRecoveryManager
*/
public void init () throws LogException
{
objectlog_.init ();
}
/**
* @see StateRecoveryManager
*/
public void register ( StateRecoverable staterecoverable )
{
if ( staterecoverable == null )
throw new IllegalArgumentException ( "null in register arg" );
Object[] states = staterecoverable.getRecoverableStates ();
if ( states != null ) {
for ( int i = 0; i < states.length; i++ ) {
staterecoverable.addFSMPreEnterListener ( this, states[i] );
}
states = staterecoverable.getFinalStates ();
for ( int i = 0; i < states.length; i++ ) {
staterecoverable.addFSMPreEnterListener ( this, states[i] );
}
}
}
/**
* @see FSMPreEnterListener
*/
public void preEnter ( FSMEnterEvent event ) throws IllegalStateException
{
Object state = event.getState ();
StateRecoverable source = (StateRecoverable) event.getSource ();
ObjectImage img = source.getObjectImage ( state );
if ( img != null ) {
//null images are not logged as per the Recoverable contract
StateObjectImage simg = new StateObjectImage ( img );
Object[] finalstates = source.getFinalStates ();
boolean delete = false;
for ( int i = 0; i < finalstates.length; i++ ) {
if ( state.equals ( finalstates[i] ) )
delete = true;
}
try {
if ( !delete )
objectlog_.flush ( simg );
else
objectlog_.delete ( simg.getId () );
} catch ( LogException le ) {
throw new IllegalStateException (
"could not flush state image " + le.getMessage () + " "
+ le.getClass ().getName () );
}
}
}
/**
* @see StateRecoveryManager
*/
public void close () throws LogException
{
objectlog_.close ();
}
/**
* @see StateRecoveryManager
*/
public StateRecoverable recover ( Object id ) throws LogException
{
StateRecoverable srec = (StateRecoverable) objectlog_.recover ( id );
if ( srec != null ) // null if not found!
register ( srec );
return srec;
}
/**
* @see StateRecoveryManager
*/
public Vector recover () throws LogException
{
Vector ret = objectlog_.recover ();
Enumeration enumm = ret.elements ();
while ( enumm.hasMoreElements () ) {
StateRecoverable srec = (StateRecoverable) enumm.nextElement ();
register ( srec );
}
return ret;
}
/**
* @see StateRecoveryManager
*/
public void delete ( Object id ) throws LogException
{
objectlog_.delete ( id );
}
}