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

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 * 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,

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package sun.tools.jconsole;

import javax.management.ObjectName;

import java.lang.management.MemoryPoolMXBean;

import java.lang.management.MemoryUsage;

import com.sun.management.GarbageCollectorMXBean;

import com.sun.management.GcInfo;

import java.util.HashMap;

import java.util.Set;

import java.util.Map;

import static java.lang.management.ManagementFactory.*;

public class MemoryPoolProxy {

    private String poolName;

    private ProxyClient client;

    private MemoryPoolMXBean pool;

    private Map<ObjectName,Long> gcMBeans;

    private GcInfo lastGcInfo;

    public MemoryPoolProxy(ProxyClient client, ObjectName poolName) throws java.io.IOException {

        this.client = client;

        this.pool = client.getMXBean(poolName, MemoryPoolMXBean.class);

        this.poolName = this.pool.getName();

        this.gcMBeans = new HashMap<ObjectName,Long>();

        this.lastGcInfo = null;

        String[] mgrNames = pool.getMemoryManagerNames();

        for (String name : mgrNames) {

            try {

                ObjectName mbeanName = new ObjectName(GARBAGE_COLLECTOR_MXBEAN_DOMAIN_TYPE +

                                                      ",name=" + name);

                if (client.isRegistered(mbeanName)) {

                    gcMBeans.put(mbeanName, new Long(0));

                }

            } catch (Exception e) {

                assert false;

            }

        }

    }

    public boolean isCollectedMemoryPool() {

        return (gcMBeans.size() != 0);

    }

    public MemoryPoolStat getStat() throws java.io.IOException {

        long usageThreshold = (pool.isUsageThresholdSupported()

                                  ? pool.getUsageThreshold()

                                  : -1);

        long collectThreshold = (pool.isCollectionUsageThresholdSupported()

                                  ? pool.getCollectionUsageThreshold()

                                  : -1);

        long lastGcStartTime = 0;

        long lastGcEndTime = 0;

        MemoryUsage beforeGcUsage = null;

        MemoryUsage afterGcUsage = null;

        long gcId = 0;

        if (lastGcInfo != null) {

            gcId = lastGcInfo.getId();

            lastGcStartTime = lastGcInfo.getStartTime();

            lastGcEndTime = lastGcInfo.getEndTime();

            beforeGcUsage = lastGcInfo.getMemoryUsageBeforeGc().get(poolName);

            afterGcUsage = lastGcInfo.getMemoryUsageAfterGc().get(poolName);

        }

        Set<Map.Entry<ObjectName,Long>> set = gcMBeans.entrySet();

        for (Map.Entry<ObjectName,Long> e : set) {

            GarbageCollectorMXBean gc =

                client.getMXBean(e.getKey(),

                                 com.sun.management.GarbageCollectorMXBean.class);

            Long gcCount = e.getValue();

            Long newCount = gc.getCollectionCount();

            if (newCount > gcCount) {

                gcMBeans.put(e.getKey(), new Long(newCount));

                lastGcInfo = gc.getLastGcInfo();

                if (lastGcInfo.getEndTime() > lastGcEndTime) {

                    gcId = lastGcInfo.getId();

                    lastGcStartTime = lastGcInfo.getStartTime();

                    lastGcEndTime = lastGcInfo.getEndTime();

                    beforeGcUsage = lastGcInfo.getMemoryUsageBeforeGc().get(poolName);

                    afterGcUsage = lastGcInfo.getMemoryUsageAfterGc().get(poolName);

                    assert(beforeGcUsage != null);

                    assert(afterGcUsage != null);

                }

            }

        }

        MemoryUsage usage = pool.getUsage();

        return new MemoryPoolStat(poolName,

                                  usageThreshold,

                                  usage,

                                  gcId,

                                  lastGcStartTime,

                                  lastGcEndTime,

                                  collectThreshold,

                                  beforeGcUsage,

                                  afterGcUsage);

    }

}