view vm-gc/command/src/main/java/com/redhat/thermostat/vm/gc/command/internal/Activator.java @ 2035:fa302aa73bae

Improve gc-command wait-for-completion logic Reusing a listener instance leads to reuse of the same CountDownLatch, which does not work as expected in a Thermostat shell use case. Additionally, a 1 second latch timeout leads to very frequent timeouts before the request response message is received, defeating the purpose of the latch. PR3241 Reviewed-by: jerboaa, omajid Review-thread: http://icedtea.classpath.org/pipermail/thermostat/2016-November/021731.html
author Andrew Azores <aazores@redhat.com>
date Tue, 22 Nov 2016 12:48:19 -0500
parents 31f274ab27a5
children a92d602216ad
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/*
 * Copyright 2012-2016 Red Hat, Inc.
 *
 * This file is part of Thermostat.
 *
 * Thermostat is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published
 * by the Free Software Foundation; either version 2, or (at your
 * option) any later version.
 *
 * Thermostat is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Thermostat; see the file COPYING.  If not see
 * <http://www.gnu.org/licenses/>.
 *
 * Linking this code with other modules is making a combined work
 * based on this code.  Thus, the terms and conditions of the GNU
 * General Public License cover the whole combination.
 *
 * As a special exception, the copyright holders of this code give
 * you permission to link this code with independent modules to
 * produce an executable, regardless of the license terms of these
 * independent modules, and to copy and distribute the resulting
 * executable under terms of your choice, provided that you also
 * meet, for each linked independent module, the terms and conditions
 * of the license of that module.  An independent module is a module
 * which is not derived from or based on this code.  If you modify
 * this code, you may extend this exception to your version of the
 * library, but you are not obligated to do so.  If you do not wish
 * to do so, delete this exception statement from your version.
 */

package com.redhat.thermostat.vm.gc.command.internal;

import java.util.Hashtable;
import java.util.Map;

import org.osgi.framework.BundleActivator;
import org.osgi.framework.BundleContext;
import org.osgi.framework.ServiceRegistration;

import com.redhat.thermostat.client.command.RequestQueue;
import com.redhat.thermostat.common.MultipleServiceTracker;
import com.redhat.thermostat.common.cli.Command;
import com.redhat.thermostat.gc.remote.common.GCRequest;
import com.redhat.thermostat.storage.dao.AgentInfoDAO;
import com.redhat.thermostat.storage.dao.VmInfoDAO;
import com.redhat.thermostat.vm.gc.common.VmGcStatDAO;

public class Activator implements BundleActivator {

    private final GCCommand gcCommand = new GCCommand(new GCCommandListenerFactoryImpl());
    private final ShowGcNameCommand showGcNameCmd = new ShowGcNameCommand();
    
    private MultipleServiceTracker showGcNameCmdTracker;
    private MultipleServiceTracker gcCommandDepsServiceTracker;
    private ServiceRegistration gcCommandRegistration;
    private ServiceRegistration showGcNameCmdRegistration;


    @Override
    public void start(BundleContext context) throws Exception {
        Class<?>[] agentVmDeps = new Class<?>[] {
                VmInfoDAO.class,
                VmGcStatDAO.class,
        };
        
        Class<?>[] serviceDeps = new Class<?>[] {
                AgentInfoDAO.class,
                VmInfoDAO.class,
                GCRequest.class,
                RequestQueue.class,
        };

        gcCommandDepsServiceTracker = new MultipleServiceTracker(context, serviceDeps, new MultipleServiceTracker.Action() {
            @Override
            public void dependenciesAvailable(Map<String, Object> services) {
                AgentInfoDAO agentDao = (AgentInfoDAO) services.get(AgentInfoDAO.class.getName());
                VmInfoDAO vmInfoDAO = (VmInfoDAO) services.get(VmInfoDAO.class.getName());
                GCRequest request = (GCRequest) services.get(GCRequest.class.getName());

                gcCommand.setServices(request, agentDao, vmInfoDAO);
            }

            @Override
            public void dependenciesUnavailable() {
                gcCommand.setServices(null, null, null);
            }
        });
        
        showGcNameCmdTracker = new MultipleServiceTracker(context, agentVmDeps, new MultipleServiceTracker.Action() {
            
            @Override
            public void dependenciesUnavailable() {
                showGcNameCmd.servicesUnavailable();
            }
            
            @Override
            public void dependenciesAvailable(Map<String, Object> services) {
                VmInfoDAO vmInfoDAO = (VmInfoDAO) services.get(VmInfoDAO.class.getName());
                VmGcStatDAO vmGcStatDAO = (VmGcStatDAO) services.get(VmGcStatDAO.class.getName());
                showGcNameCmd.setVmInfo(vmInfoDAO);
                showGcNameCmd.setVmGcStat(vmGcStatDAO);
            }
        });

        gcCommandDepsServiceTracker.open();
        showGcNameCmdTracker.open();

        Hashtable<String,String> properties = new Hashtable<>();
        properties.put(Command.NAME, GCCommand.REGISTER_NAME);
        gcCommandRegistration = context.registerService(Command.class.getName(), gcCommand, properties);
        properties = new Hashtable<>();
        properties.put(Command.NAME, ShowGcNameCommand.REGISTER_NAME);
        showGcNameCmdRegistration = context.registerService(Command.class.getName(), showGcNameCmd, properties);
    }

    @Override
    public void stop(BundleContext context) throws Exception {
        gcCommandDepsServiceTracker.close();
        showGcNameCmdTracker.close();
        gcCommandRegistration.unregister();
        showGcNameCmdRegistration.unregister();
    }
}