/**
* 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.hama.util;
import java.io.IOException;
import java.util.List;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.conf.Configuration;
import org.apache.hama.HamaConfiguration;
import org.apache.hama.bsp.BSPMaster;
import org.apache.hama.bsp.GroomServer;
public class ClusterUtil {
private static final Log LOG = LogFactory.getLog(ClusterUtil.class);
/**
* Data Structure to hold GroomServer Thread and GroomServer instance
*/
public static class GroomServerThread extends Thread {
private final GroomServer groomServer;
public GroomServerThread(final GroomServer r, final int index) {
super(r, "GroomServer:" + index);
this.groomServer = r;
}
/** @return the groom server */
public GroomServer getGroomServer() {
return this.groomServer;
}
/**
* Block until the groom server has come online, indicating it is ready to
* be used.
*/
public void waitForServerOnline() {
while (!groomServer.isRunning()) {
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
// continue waiting
}
}
}
}
/**
* Creates a {@link GroomServerThread}. Call 'start' on the returned thread to
* make it run.
*
* @param c Configuration to use.
* @param hrsc Class to create.
* @param index Used distingushing the object returned.
* @throws IOException
* @return Groom server added.
*/
public static ClusterUtil.GroomServerThread createGroomServerThread(
final Configuration c, final Class<? extends GroomServer> hrsc,
final int index) throws IOException {
GroomServer server;
try {
server = hrsc.getConstructor(Configuration.class).newInstance(c);
} catch (Exception e) {
IOException ioe = new IOException();
ioe.initCause(e);
throw ioe;
}
return new ClusterUtil.GroomServerThread(server, index);
}
/**
* Start the cluster.
*
* @param m the BSP master
* @param conf cluster configuration to be used
* @param groomservers list of threads holding groom servers
* @return Address to use contacting master.
* @throws InterruptedException
* @throws IOException
*/
public static String startup(final BSPMaster m,
final List<ClusterUtil.GroomServerThread> groomservers, Configuration conf)
throws IOException, InterruptedException {
if (m != null) {
BSPMaster.startMaster((HamaConfiguration) conf);
}
if (groomservers != null) {
for (ClusterUtil.GroomServerThread t : groomservers) {
t.start();
}
}
return m == null ? null : BSPMaster.getAddress(conf).getHostName();
}
public static void shutdown(BSPMaster master,
List<GroomServerThread> groomThreads, Configuration conf) {
LOG.debug("Shutting down HAMA Cluster");
// TODO:
}
}