cern.c2mon.server.cache.dbaccess.impl.CacheDbLifecycle.java Source code

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Here is the source code for cern.c2mon.server.cache.dbaccess.impl.CacheDbLifecycle.java

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/******************************************************************************
 * Copyright (C) 2010-2016 CERN. All rights not expressly granted are reserved.
 *
 * This file is part of the CERN Control and Monitoring Platform 'C2MON'.
 * C2MON is free software: you can redistribute it and/or modify it under the
 * terms of the GNU Lesser General Public License as published by the Free
 * Software Foundation, either version 3 of the license.
 *
 * C2MON 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 Lesser General Public License for
 * more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with C2MON. If not, see <http://www.gnu.org/licenses/>.
 *****************************************************************************/
package cern.c2mon.server.cache.dbaccess.impl;

import java.sql.SQLException;

import javax.sql.DataSource;

import org.apache.commons.dbcp.BasicDataSource;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.context.SmartLifecycle;
import org.springframework.jmx.export.annotation.ManagedOperation;
import org.springframework.jmx.export.annotation.ManagedResource;
import org.springframework.stereotype.Service;

import cern.c2mon.server.common.config.ServerConstants;

/**
 * Manages the closing of the cache DB connections.
 * @author Mark Brightwell
 *
 */
@Service
@ManagedResource(objectName = "cern.c2mon:type=datasource,name=cacheDbLifecycle")
public class CacheDbLifecycle implements SmartLifecycle {

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

    /**
     * The cache datasource to close down.
     */
    private DataSource cacheDataSource;

    /**
     * Only designed to
     */
    private volatile boolean started = false;

    @Autowired
    public CacheDbLifecycle(@Qualifier("cacheDataSource") DataSource cacheDataSource) {
        super();
        this.cacheDataSource = cacheDataSource;
    }

    /**
     * For management only.
     * @return the number of active DB connections in the cache datasource pool
     */
    @ManagedOperation(description = "The number of active DB connections in the cache datasource pool (only works for Apache BasicDataSource)")
    public int getNumActiveDbConnections() {
        if (cacheDataSource instanceof BasicDataSource)
            return ((BasicDataSource) cacheDataSource).getNumActive();
        else
            return 0;
    }

    @Override
    public boolean isRunning() {
        return started;
    }

    /**
     * Nothing to start, as already done in datasource initialisation.
     */
    @Override
    public void start() {
        started = true;
    }

    @Override
    public void stop() {
        LOGGER.info("Closing down cache DB connections (only available for Apache BasicDataSource)");
        try {
            if (cacheDataSource instanceof BasicDataSource)
                ((BasicDataSource) cacheDataSource).close();
        } catch (SQLException ex) {
            LOGGER.error("Exception caught while closing down cache DB connections.", ex);
            ex.printStackTrace();
        }
    }

    @Override
    public boolean isAutoStartup() {
        return true;
    }

    /**
     * Smart lifecycle stop implementation.
     * Closes the DB connection pool.
     */
    @Override
    public void stop(Runnable arg0) {
        stop();
        arg0.run();
    }

    @Override
    public int getPhase() {
        return ServerConstants.PHASE_STOP_LAST - 1;
    }

}