com.alibaba.wasp.util.JVMClusterUtil.java Source code

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/**
 * Copyright The Apache Software Foundation
 *
 * 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 com.alibaba.wasp.util;

import com.alibaba.wasp.fserver.FServer;
import com.alibaba.wasp.master.FMaster;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.util.Threads;

import java.io.IOException;
import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;
import java.util.List;

/**
 * Utility used running a cluster all in the one JVM.
 */
public class JVMClusterUtil {
    private static final Log LOG = LogFactory.getLog(JVMClusterUtil.class);

    /**
     * Datastructure to hold FServer Thread and FServer instance
     */
    public static class FServerThread extends Thread {
        private final FServer fserver;

        public FServerThread(final FServer r, final int index) {
            super(r, "FServer:" + index + ";" + r.getServerName());
            this.fserver = r;
        }

        /** @return the fserver */
        public FServer getFServer() {
            return this.fserver;
        }

        /**
         * Block until the fserver has come online, indicating it is ready
         * to be used.
         */
        public void waitForServerOnline() {
            // The server is marked online after the init method completes inside of
            // the fserver#run method. fserver#init can fail for whatever entityGroup.
            // In those cases, we'll jump out of the run without setting online flag.
            // Check stopRequested so we don't wait here a flag that will never be
            // flipped.
            fserver.waitForServerOnline();
        }
    }

    /**
     * Creates a {@link FServerThread}.
     * Call 'start' on the returned thread to make it run.
     * @param c Configuration to use.
     * @param hrsc Class to create.
     * @param index Used distinguishing the object returned.
     * @throws java.io.IOException
     * @return FServer added.
     */
    public static JVMClusterUtil.FServerThread createFServerThread(final Configuration c,
            final Class<? extends FServer> hrsc, final int index) throws IOException {
        FServer server;
        try {
            Constructor<? extends FServer> ctor = hrsc.getConstructor(Configuration.class);
            ctor.setAccessible(true);
            server = ctor.newInstance(c);
        } catch (InvocationTargetException ite) {
            Throwable target = ite.getTargetException();
            throw new RuntimeException("Failed construction of FServer: " + hrsc.toString()
                    + ((target.getCause() != null) ? target.getCause().getMessage() : ""), target);
        } catch (Exception e) {
            IOException ioe = new IOException();
            ioe.initCause(e);
            throw ioe;
        }
        return new JVMClusterUtil.FServerThread(server, index);
    }

    /**
     * Datastructure to hold Master Thread and Master instance
     */
    public static class MasterThread extends Thread {
        private final FMaster master;

        public MasterThread(final FMaster m, final int index) {
            super(m, "Master:" + index + ";" + m.getServerName());
            this.master = m;
        }

        /** @return the master */
        public FMaster getMaster() {
            return this.master;
        }
    }

    /**
     * Creates a {@link MasterThread}.
     * Call 'start' on the returned thread to make it run.
     * @param c Configuration to use.
     * @param hmc Class to create.
     * @param index Used distinguishing the object returned.
     * @throws java.io.IOException
     * @return Master added.
     */
    public static JVMClusterUtil.MasterThread createMasterThread(final Configuration c,
            final Class<? extends FMaster> hmc, final int index) throws IOException {
        FMaster server;
        try {
            server = hmc.getConstructor(Configuration.class).newInstance(c);
        } catch (InvocationTargetException ite) {
            Throwable target = ite.getTargetException();
            throw new RuntimeException("Failed construction of Master: " + hmc.toString()
                    + ((target.getCause() != null) ? target.getCause().getMessage() : ""), target);
        } catch (Exception e) {
            IOException ioe = new IOException();
            ioe.initCause(e);
            throw ioe;
        }
        return new JVMClusterUtil.MasterThread(server, index);
    }

    private static JVMClusterUtil.MasterThread findActiveMaster(List<MasterThread> masters) {
        for (JVMClusterUtil.MasterThread t : masters) {
            if (t.master.isActiveMaster()) {
                return t;
            }
        }

        return null;
    }

    /**
     * Start the cluster.  Waits until there is a primary master initialized
     * and returns its address.
     * @param masters
     * @param fservers
     * @return Address to use contacting primary master.
     */
    public static String startup(final List<MasterThread> masters, final List<FServerThread> fservers)
            throws IOException {

        if (masters == null || masters.isEmpty()) {
            return null;
        }

        for (JVMClusterUtil.MasterThread t : masters) {
            t.start();
        }

        // Wait for an active master
        // having an active master before starting the fserver threads allows
        //  then to succeed on their connection to master
        long startTime = System.currentTimeMillis();
        while (findActiveMaster(masters) == null) {
            try {
                Thread.sleep(100);
            } catch (InterruptedException ignored) {
            }
            if (System.currentTimeMillis() > startTime + 30000) {
                throw new RuntimeException("Master not active after 30 seconds");
            }
        }

        if (fservers != null) {
            for (JVMClusterUtil.FServerThread t : fservers) {
                t.start();
            }
        }

        // Wait for an active master to be initialized (implies being master)
        //  with this, when we return the cluster is complete
        startTime = System.currentTimeMillis();
        while (true) {
            JVMClusterUtil.MasterThread t = findActiveMaster(masters);
            if (t != null && t.master.isInitialized()) {
                return t.master.getServerName().toString();
            }
            if (System.currentTimeMillis() > startTime + 200000) {
                throw new RuntimeException("Master not initialized after 200 seconds");
            }
            try {
                Thread.sleep(100);
            } catch (InterruptedException ignored) {
                // Keep waiting
            }
        }
    }

    /**
     * @param masters
     * @param fservers
     */
    public static void shutdown(final List<MasterThread> masters, final List<FServerThread> fservers)
            throws IOException {
        LOG.debug("Shutting down HBase Cluster");
        if (masters != null) {
            // Do backups first.
            JVMClusterUtil.MasterThread activeMaster = null;
            for (JVMClusterUtil.MasterThread t : masters) {
                if (!t.master.isActiveMaster()) {
                    t.master.stopMaster();
                } else {
                    activeMaster = t;
                }
            }
            // Do active after.
            if (activeMaster != null)
                activeMaster.master.shutdown();
        }
        if (fservers != null) {
            for (FServerThread t : fservers) {
                if (t.isAlive()) {
                    try {
                        t.getFServer().stop("Shutdown requested");
                        t.join();
                    } catch (InterruptedException e) {
                        // continue
                    }
                }
            }
        }
        if (masters != null) {
            for (JVMClusterUtil.MasterThread t : masters) {
                while (t.master.isAlive()) {
                    try {
                        // The below has been replaced to debug sometime hangs on end of
                        // tests.
                        // this.master.join():
                        Threads.threadDumpingIsAlive(t.master.getThread());
                    } catch (InterruptedException e) {
                        // continue
                    }
                }
            }
        }
        LOG.info("Shutdown of " + ((masters != null) ? masters.size() : "0") + " master(s) and "
                + ((fservers != null) ? fservers.size() : "0") + " fserver(s) complete");
    }
}