/*

 * Copyright (c) 2004, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code 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

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package sun.jvmstat.perfdata.monitor;

import java.util.List;

import java.lang.reflect.*;

import java.io.*;

import sun.jvmstat.monitor.*;

import sun.jvmstat.monitor.remote.*;

import sun.jvmstat.monitor.event.VmListener;

/**

 * Base class for all MonitoredVm implementations that utilize the

 * HotSpot PerfData instrumentation buffer as the communications

 * mechanism to the target Java Virtual Machine.

 *

 * @author Brian Doherty

 * @since 1.5

 */

public abstract class AbstractMonitoredVm implements BufferedMonitoredVm {

    /**

     * The VmIdentifier for the target.

     */

    protected VmIdentifier vmid;

    /**

     * The shared memory instrumentation buffer for the target.

     */

    protected AbstractPerfDataBuffer pdb;

    /**

     * The sampling interval, if the instrumentation buffer is acquired

     * by sampling instead of shared memory mechanisms.

     */

    protected int interval;

    /**

     * Create an AbstractMonitoredVm instance.

     *

     * @param vmid the VmIdentifier for the target

     * @param interval the initial sampling interval

     */

    public AbstractMonitoredVm(VmIdentifier vmid, int interval)

           throws MonitorException {

        this.vmid = vmid;

        this.interval = interval;

    }

    /**

     * {@inheritDoc}

     */

    public VmIdentifier getVmIdentifier() {

        return vmid;

    }

    /**

     * {@inheritDoc}

     */

    public Monitor findByName(String name) throws MonitorException {

        return pdb.findByName(name);

    }

    /**

     * {@inheritDoc}

     */

    public List<Monitor> findByPattern(String patternString) throws MonitorException {

        return pdb.findByPattern(patternString);

    }

    /**

     * {@inheritDoc}

     */

    public void detach() {

        /*

         * no default action required because the detach operation for the

         * native byte buffer is managed by the sun.misc.Perf class.

         */

    }

    /* ---- Methods to support polled MonitoredVm Implementations ----- */

    /**

     * {@inheritDoc}

     */

    public void setInterval(int interval) {

        this.interval = interval;

    }

    /**

     * {@inheritDoc}

     */

    public int getInterval() {

        return interval;

    }

    /**

     * {@inheritDoc}

     */

    public void setLastException(Exception e) {

        // XXX: implement

    }

    /**

     * {@inheritDoc}

     */

    public Exception getLastException() {

        // XXX: implement

        return null;

    }

    /**

     * {@inheritDoc}

     */

    public void clearLastException() {

        // XXX: implement

    }

    /**

     * {@inheritDoc}

     */

    public boolean isErrored() {

        // XXX: implement

        return false;

    }

    /**

     * Get a list of the inserted and removed monitors since last called.

     *

     * @return MonitorStatus - the status of available Monitors for the

     *                         target Java Virtual Machine.

     * @throws MonitorException Thrown if communications errors occur

     *                          while communicating with the target.

     */

    public MonitorStatus getMonitorStatus() throws MonitorException {

        return pdb.getMonitorStatus();

    }

    /* --------------- Methods to support VmListeners ----------------- */

    /**

     * {@inheritDoc}

     */

    public abstract void addVmListener(VmListener l);

    /**

     * {@inheritDoc}

     */

    public abstract void removeVmListener(VmListener l);

    /* ---- Methods to support BufferedMonitoredVm Implementations ---- */

    /**

     * {@inheritDoc}

     */

    public byte[] getBytes() {

        return pdb.getBytes();

    }

    /**

     * {@inheritDoc}

     */

    public int getCapacity() {

        return pdb.getCapacity();

    }

}