/**
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.apache.activemq.apollo.util;
import org.fusesource.hawtdispatch.internal.util.RunnableCountDownLatch;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.util.List;
/**
* A helper class used to stop a bunch of services, catching and logging any
* exceptions and then throwing the first exception when everything is stoped.
*
* @version $Revision: 1.1 $
*/
public class ServiceStopper {
private Throwable firstException;
/**
* Stops the given service, catching any exceptions that are thrown.
*/
public void stop(Service service) {
try {
if (service != null) {
RunnableCountDownLatch latch = new RunnableCountDownLatch(1);
service.stop(latch);
latch.await();
}
} catch (Exception e) {
onException(service, e);
}
}
/**
* Performs the given code to stop some service handling the exceptions
* which may be thrown properly
*/
public void run(Callback stopClosure) {
try {
stopClosure.execute();
} catch (Throwable e) {
onException(stopClosure, e);
}
}
/**
* Stops a list of services
*/
public void stopServices(List<Service> services) throws Exception {
RunnableCountDownLatch latch = new RunnableCountDownLatch(services.size());
for (int i = 0; i < services.size(); i++) {
Service service = services.get(i);
try {
service.stop(latch);
} catch (Exception e) {
onException(service, e);
}
}
if( firstException==null ) {
latch.await();
}
}
public void onException(Object owner, Throwable e) {
logError(owner, e);
if (firstException == null) {
firstException = e;
}
}
/**
* Throws the first exception that was thrown if there was one.
*/
public void throwFirstException() throws Exception {
if (firstException != null) {
if (firstException instanceof Exception) {
Exception e = (Exception)firstException;
throw e;
} else if (firstException instanceof RuntimeException) {
RuntimeException e = (RuntimeException)firstException;
throw e;
} else {
throw new RuntimeException("Unknown type of exception: " + firstException, firstException);
}
}
}
protected void logError(Object service, Throwable e) {
Logger log = LoggerFactory.getLogger(service.getClass());
log.error("Could not stop service: " + service + ". Reason: " + e, e);
}
}