/*
* #%L
* Talend :: ESB :: Job :: Controller
* %%
* Copyright (C) 2011 - 2012 Talend Inc.
* %%
* 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.
* #L%
*/
package org.talend.esb.job.controller.internal;
import java.util.logging.Level;
import java.util.logging.Logger;
import org.talend.esb.job.controller.internal.MessageExchangeBuffer.BufferStoppedException;
import routines.system.api.ESBJobInterruptedException;
import routines.system.api.ESBProviderCallback;
import routines.system.api.TalendESBJob;
/**
* Callback implementation responsible for one Job. It provides a bridge between the
* {@link MessageExchangeBuffer buffer} holding the requests and the job retrieving a request. I also
* responsible to assign the response to the request as soon as available.
* <code>RuntimeESBProviderCallback</code> is an active object and meant to be run in its own {@link Thread}.
*
*/
public class RuntimeESBProviderCallback implements ESBProviderCallback, Runnable {
private static final Logger LOG =
Logger.getLogger(RuntimeESBProviderCallback.class.getName());
private MessageExchangeBuffer messageExchanges;
private TalendESBJob job;
private final String name;
private MessageExchange currentExchange;
private String[] arguments;
/**
* Creates a new callback.
*
* @param messageExchanges
* the buffer from which to retrieve the requests for the job.
* @param esbJob
* the job for which this callback is responsible , must not be <code>null</code>
* @param arguments
* arguments to be passed to the job when starting it, must not be <code>null</code>
*/
public RuntimeESBProviderCallback(
MessageExchangeBuffer messageExchanges,
TalendESBJob esbJob,
String jobName,
String[] arguments) {
this.messageExchanges = messageExchanges;
job = esbJob;
name = jobName;
this.arguments = arguments;
}
/**
* Retrieves a request from the buffer and forwards it to the {@link TalendESBJob job} requesting it.
*
* @return the request retrieved from the buffer
*/
@Override
public Object getRequest() throws ESBJobInterruptedException {
try {
currentExchange = messageExchanges.take();
} catch (BufferStoppedException e) {
Thread.currentThread().interrupt();
throw new ESBJobInterruptedException("Job canceled.");
} catch (InterruptedException e) {
Thread.currentThread().interrupt();
throw new ESBJobInterruptedException("Job canceled.");
}
return currentExchange.getRequest();
}
/**
* {@inheritDoc}
*/
@Override
public void sendResponse(Object response) {
currentExchange.setResponse(response);
}
/**
* Starts the @link TalendESBJob job} for which this callback is responsible. The job is restarted if it
* returns back, except the {@link Thread} was interrupted or the buffer was closed.
*/
@Override
public void run() {
if (LOG.isLoggable(Level.INFO)) {
LOG.info("Calling run to start ESB job instance " + job + " for job with name " + name);
}
ClassLoader oldContextCL = Thread.currentThread().getContextClassLoader();
try {
Thread.currentThread().setContextClassLoader(job.getClass().getClassLoader());
while (true) {
if (Thread.interrupted()) {
return;
}
LOG.info("Starting ESB job instance " + job + " for job with name " + name);
int ret = job.runJobInTOS(arguments);
LOG.info("ESB job instance " + job + " with name " + name + " finished, return code is "
+ ret);
if (ret != 0) {
break;
}
}
} catch (RuntimeException ex) {
ex.printStackTrace();
LOG.log(Level.SEVERE, "RuntimeException when invoking runJobInTOS()", ex);
} finally {
Thread.currentThread().setContextClassLoader(oldContextCL);
}
}
@Override
public String toString() {
return "RuntimeESBProviderCallback[" + System.identityHashCode(this) + "] for job " + job;
}
public static class MessageExchange {
private Object request;
private Object response;
private boolean ready;
public MessageExchange(Object request) {
this.request = request;
}
public Object getRequest() {
return request;
}
public void setResponse(Object response) {
synchronized (this) {
this.response = response;
ready = true;
notifyAll();
}
}
public Object waitForResponse() throws InterruptedException {
synchronized (this) {
while (!ready) {
wait();
}
}
return response;
}
}
}