fr.jetoile.hadoopunit.HadoopBootstrap.java Source code

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Here is the source code for fr.jetoile.hadoopunit.HadoopBootstrap.java

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/*
 * 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 fr.jetoile.hadoopunit;

import com.google.common.collect.Lists;
import fr.jetoile.hadoopunit.component.Bootstrap;
import fr.jetoile.hadoopunit.exception.NotFoundServiceException;
import org.apache.commons.configuration.Configuration;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.*;
import java.nio.charset.Charset;
import java.util.*;

public enum HadoopBootstrap {
    INSTANCE;

    final private static Logger LOGGER = LoggerFactory.getLogger(HadoopBootstrap.class);

    private Configuration configuration;
    List<Bootstrap> componentsToStart = new ArrayList<>();
    List<Bootstrap> manualComponentsToStart = new ArrayList<>();
    List<Bootstrap> componentsToStop = new ArrayList<>();
    List<Bootstrap> manualComponentsToStop = new ArrayList<>();

    private ServiceLoader<Bootstrap> commandLoader = ServiceLoader.load(Bootstrap.class);
    private Map<String, Bootstrap> commands = new HashMap<>();

    HadoopBootstrap() {
        commands.clear();
        commandLoader.reload();
        Iterator<Bootstrap> commandsIterator = commandLoader.iterator();

        while (commandsIterator.hasNext()) {
            Bootstrap command = commandsIterator.next();
            commands.put(command.getName(), command);
        }

        Arrays.asList(Component.values()).stream().forEach(c -> {
            if (commands.containsKey(c.name())) {
                componentsToStart.add(commands.get(c.name()));
            }
        });

        componentsToStop = Lists.newArrayList(this.componentsToStart);
        Collections.reverse(componentsToStop);

        Runtime.getRuntime().addShutdownHook(new Thread() {
            public void run() {
                LOGGER.info("All services are going to be stopped");
                stopAll();
            }
        });
    }

    public Bootstrap getService(Component c) throws NotFoundServiceException {
        if (commands.containsKey(c.name())) {
            return commands.get(c.name());
        } else {
            throw new NotFoundServiceException("unable to find service " + c.name());
        }

    }

    public void startAll() {
        if (manualComponentsToStart.isEmpty()) {
            internalStart(componentsToStart);
        } else {
            internalStart(manualComponentsToStart);
        }
    }

    public void stopAll() {
        if (manualComponentsToStop.isEmpty()) {
            internalStop(componentsToStop);
        } else {
            manualComponentsToStop = Lists.newArrayList(this.manualComponentsToStart);
            Collections.reverse(manualComponentsToStop);
            internalStop(manualComponentsToStop);
        }
    }

    public HadoopBootstrap add(Component component) throws NotFoundServiceException {
        manualComponentsToStart.add(getService(component));
        return this;
    }

    private void internalStart(List<Bootstrap> componentsToStart) {
        componentsToStart.stream().forEach(c -> {
            startService(c);
        });
        HadoopUtils.printBanner(System.out);
        componentsToStart.stream()
                .forEach(c -> System.out.println("\t\t - " + c.getName() + " " + c.getProperties()));
        System.out.println();
    }

    private void internalStop(List<Bootstrap> componentsToStop) {
        componentsToStop.stream().forEach(c -> {
            stopService(c);
        });
    }

    private void startService(Bootstrap c) {
        c.start();
    }

    private void stopService(Bootstrap c) {
        c.stop();
    }

}