/**
*
* Copyright 2004 Hiram Chirino
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* 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.
* See the License for the specific language governing permissions and
* limitations under the License.
*
**/
package org.codehaus.activemq.service.impl;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.codehaus.activemq.broker.Broker;
import org.codehaus.activemq.service.Transaction;
import org.codehaus.activemq.service.TransactionTask;
import javax.transaction.xa.XAException;
import java.io.Externalizable;
import java.io.IOException;
import java.io.ObjectInput;
import java.io.ObjectOutput;
import java.util.ArrayList;
import java.util.Iterator;
/**
* Keeps track of all the actions the need to be done when
* a transaction does a commit or rollback.
*
* @version $Revision: 1.1 $
*/
public abstract class AbstractTransaction implements Transaction, Externalizable {
static final private Log log = LogFactory.getLog(AbstractTransaction.class);
static final public byte START_STATE = 0; // can go to: 1,2,3
static final public byte IN_USE_STATE = 1; // can go to: 2,3
static final public byte PREPARED_STATE = 2; // can go to: 3
static final public byte FINISHED_STATE = 3;
private ArrayList prePrepareTasks = new ArrayList();
private ArrayList postCommitTasks = new ArrayList();
private ArrayList postRollbackTasks = new ArrayList();
private byte state = START_STATE;
private transient Broker broker;
protected AbstractTransaction(Broker broker) {
this.broker = broker;
}
public Broker getBroker() {
return broker;
}
/**
* Called after deserialization to register the broker
*
* @param broker
*/
public void setBroker(Broker broker) {
this.broker = broker;
}
public byte getState() {
return state;
}
public void setState(byte state) {
this.state = state;
}
public void addPostCommitTask(TransactionTask r) {
postCommitTasks.add(r);
if (state == START_STATE) {
state = IN_USE_STATE;
}
}
public void addPostRollbackTask(TransactionTask r) {
postRollbackTasks.add(r);
if (state == START_STATE) {
state = IN_USE_STATE;
}
}
public void addPrePrepareTask(TransactionTask r) {
prePrepareTasks.add(r);
if (state == START_STATE) {
state = IN_USE_STATE;
}
}
public void prePrepare() throws Throwable {
// Is it ok to call prepare now given the state of the
// transaction?
switch (state) {
case START_STATE:
case IN_USE_STATE:
break;
default:
XAException xae = new XAException("Prepare cannot be called now.");
xae.errorCode = XAException.XAER_PROTO;
throw xae;
}
// Run the prePrepareTasks
for (Iterator iter = prePrepareTasks.iterator(); iter.hasNext();) {
TransactionTask r = (TransactionTask) iter.next();
r.execute(broker);
}
}
protected void postCommit() throws Throwable {
// Run the postCommitTasks
for (Iterator iter = postCommitTasks.iterator(); iter.hasNext();) {
TransactionTask r = (TransactionTask) iter.next();
r.execute(broker);
}
}
public void postRollback() throws Throwable {
// Run the postRollbackTasks
for (Iterator iter = postRollbackTasks.iterator(); iter.hasNext();) {
TransactionTask r = (TransactionTask) iter.next();
r.execute(broker);
}
}
public void readExternal(ObjectInput in) throws IOException, ClassNotFoundException {
state = in.readByte();
prePrepareTasks = readTaskList(in);
postCommitTasks = readTaskList(in);
postRollbackTasks = readTaskList(in);
}
public void writeExternal(ObjectOutput out) throws IOException {
out.writeByte(state);
writeTaskList(prePrepareTasks, out);
writeTaskList(postCommitTasks, out);
writeTaskList(postRollbackTasks, out);
}
public String toString() {
return super.toString() + "[prePrepares=" + prePrepareTasks + "; postCommits=" + postCommitTasks
+ "; postRollbacks=" + postRollbackTasks + "]";
}
// Implementation methods
//-------------------------------------------------------------------------
protected ArrayList readTaskList(ObjectInput in) throws IOException {
int size = in.readInt();
ArrayList answer = new ArrayList(size);
for (int i = 0; i < size; i++) {
answer.add(readTask(in));
}
return answer;
}
protected void writeTaskList(ArrayList tasks, ObjectOutput out) throws IOException {
int size = tasks.size();
out.writeInt(size);
for (int i = 0; i < size; i++) {
writeTask((TransactionTask) tasks.get(i), out);
}
}
protected TransactionTask readTask(ObjectInput in) throws IOException {
return PacketTransactionTask.readTask(in);
}
protected void writeTask(TransactionTask task, ObjectOutput out) throws IOException {
PacketTransactionTask.writeTask(task, out);
}
}