org.jbr.commons.container.SpringContainerManager.java Source code

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Here is the source code for org.jbr.commons.container.SpringContainerManager.java

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/**
 * Copyright (C) - 2013 jbrule
 * 
 * This program 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 3 of the License, or (at your option) any later
 * version.
 * 
 * This program 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
 * this program. If not, see <http://www.gnu.org/licenses/>
 */
package org.jbr.commons.container;

import java.util.Calendar;
import java.util.Date;

import javax.annotation.PostConstruct;
import javax.annotation.Resource;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.context.ApplicationContext;
import org.springframework.context.Lifecycle;
import org.springframework.context.support.AbstractApplicationContext;
import org.springframework.jmx.export.annotation.ManagedAttribute;
import org.springframework.jmx.export.annotation.ManagedOperation;
import org.springframework.jmx.export.annotation.ManagedResource;
import org.springframework.stereotype.Component;

/**
 * Manages a Spring Container.
 * 
 * @author <a href="mailto:brulejr@gmail.com">Jon Brule</a>
 */
@Component
@ManagedResource
public class SpringContainerManager implements Lifecycle {

    private final Logger log = LoggerFactory.getLogger(getClass().getSimpleName());

    @Resource
    private ApplicationContext context;

    private Calendar startTimestamp;
    private Calendar stopTimestamp;

    @ManagedAttribute(description = "When the Spring Container was last started")
    public Date getStartTimestamp() {
        return (startTimestamp != null) ? startTimestamp.getTime() : null;
    }

    @ManagedAttribute(description = "When the Spring Container was last stopped")
    public Date getStopTimestamp() {
        return (stopTimestamp != null) ? stopTimestamp.getTime() : null;
    }

    @PostConstruct
    public void init() {

    }

    @Override
    @ManagedAttribute(description = "Returns true if the Spring ApplicationContext is running")
    public boolean isRunning() {
        return ((AbstractApplicationContext) context).isRunning();
    }

    @Override
    public void start() {
        log.info("Starting {}", getClass().getSimpleName());
        startTimestamp = Calendar.getInstance();
    }

    @ManagedOperation(description = "Start the SpringContainer if it is not already running.")
    public void startContainer() {
        if (log.isInfoEnabled()) {
            log.info("Starting SpringContainer...");
        }

        final AbstractApplicationContext ctx = (AbstractApplicationContext) context;
        if (!ctx.isRunning()) {
            ctx.start();
            startTimestamp = Calendar.getInstance();
            if (log.isInfoEnabled()) {
                log.info("SpringContainer started !!!");
            }
        } else {
            if (log.isInfoEnabled()) {
                log.info("SpringContainer already running !!!");
            }
        }
    }

    @Override
    public void stop() {
        log.info("Stopping {}", getClass().getSimpleName());
    }

    @ManagedOperation(description = "Stop the SpringContainer, if it is running.")
    public void stopContainer() {
        if (log.isInfoEnabled()) {
            log.info("Stopping SpringContainer...");
        }
        final AbstractApplicationContext ctx = (AbstractApplicationContext) context;
        if (ctx.isRunning()) {
            ctx.stop();
            stopTimestamp = Calendar.getInstance();
            if (log.isInfoEnabled()) {
                log.info("SpringContainer stopped !!!");
            }
        } else {
            if (log.isInfoEnabled()) {
                log.info("SpringContainer already stopped !!!");
            }
        }
    }

    @ManagedOperation(description = "Shutdown the application - terminates the JVM")
    public void shutdown() {
        if (log.isInfoEnabled()) {
            log.info("Closing SpringContainer...");
        }

        ((AbstractApplicationContext) context).close();
        context = null;

        if (log.isInfoEnabled()) {
            log.info("Closed SpringContainer - Terminating JVM!!!");
        }
        System.exit(0);
    }

}