Example - ObjectTreeMonitor

gcRadar ObjectTreeMonitor Example

GCMoniterTest.java

/*This file is part of gcRadar.

gcRadar 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 version 3 of the License.

gcRadar 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 gcRadar.  If not, see <http://www.gnu.org/licenses/>.
 */

package test;

import java.util.Set;

import test.ds.TreeTester_1;

import com.gcr.callbacks.GcRadarCallback;
import com.gcr.monitors.ObjectTreeMonitor;
import com.gcr.structs.AbstractObjectRefrenceKey;
import com.gcr.structs.annotation.GcRadarNotToInclude;
import com.gcr.structs.annotation.GcRadarToInclude;

public class GCMoniterTest implements GcRadarCallback
{
    public static void main(String[] args)
    {
        GCMoniterTest gcMoniterTest = new GCMoniterTest();

        System.out.println("========Starting Optimistic Test=========");
        gcMoniterTest.doTestTree(true);

        System.gc();
        System.out.println("========Ending Optimistic Test=========");

        System.out.println();

        System.out.println("========Starting Pesimistic Test=========");
        gcMoniterTest.doTestTree(false);

        System.gc();
        System.out.println("========Ending Pesimistic Test=========");

    }

    private void doTestTree(boolean isOptimistic)
    {
        System.out.println("GCMoniterTest.doTestTree(), isOptimistic - " + isOptimistic);

        // Create complex object to be added to monitoring
        TreeTester_3 tt3 = new TreeTester_3();

        // Instantiate an ObjectTreeMonitor instance using the method parameter
        // to set optimism
        ObjectTreeMonitor oTreeMonitor = new ObjectTreeMonitor(isOptimistic);

        // Add the complex object to the monitoring list, provide a string-key
        // that will be used as an alias name for this object and its comprising
        // members during monitoring.
        oTreeMonitor.addObject(tt3, "tree_tester_3", this);

        // Start the background monitoring thread. Events will be received only
        // after this method call.
        oTreeMonitor.startMonitoring();

        System.out.println("Number of pending objects - " + oTreeMonitor.getPendingObjectsCount());

        // Orphan the object so that the Garbage collector can collect it. This
        // has been done artificially for this example
        tt3 = null;

        // wait for the garbage collector to work
        try
        {
            Thread.sleep(5000);
        }
        catch (InterruptedException e)
        {
            e.printStackTrace();
        }

        System.out.println("Number of pending objects - " + oTreeMonitor.getPendingObjectsCount());

        // If any pending objecta are still left then print there string-keys
        Set<AbstractObjectRefrenceKey<Object>> pendingObjects = oTreeMonitor.getPendingObjects();
        if (pendingObjects.size() != 0)
        {
            System.out.println("Following are the keys of the pending objects ");
            for (AbstractObjectRefrenceKey<Object> a : pendingObjects)
            {
                System.out.println(a.getObjRefrenceKey());
            }
        }

        oTreeMonitor.stopMonitoring();
    }

    @Override
    public <T> void objectReclaimedByGC(AbstractObjectRefrenceKey<T> refrenceKey)
    {
        System.out.println(" - GCed - " + refrenceKey.getObjRefrenceKey() + " at " + refrenceKey.getPhantomCallbackTime());
    }

    @Override
    public <T> void noSurvivingRefrence(AbstractObjectRefrenceKey<T> objWrapper)
    {
        System.out.println(" - About to GC - " + objWrapper.getObjRefrenceKey() + " at " + objWrapper.getWeakCallbackTime());
    }

    // This annotation will cause the monitor to prevent the members of this
    // class from being added to monitoring in the Optimistic mode
    @GcRadarNotToInclude
    class TreeTester_2 extends TreeTester_1
    {
        public int publicPrimInt_2;
        private int privatePrimInt_2;
        protected int protectedPrimInt_2;
        int defaultPrimInt_2;

        public Integer publicInt_2 = new Integer(5);
        private Integer privateInt_2 = new Integer(5);
        protected Integer protectedInt_2 = new Integer(5);
        Integer defaultInt_2 = new Integer(5);
    }

    class TreeTester_3 extends TreeTester_2
    {
        public int publicPrimInt_3;
        private int privatePrimInt_3;
        protected int protectedPrimInt_3;
        int defaultPrimInt_3;

        // This annotation will cause this member to be included to monitoring
        // in the pessimistic mode of operation
        @GcRadarToInclude
        public Integer publicInt_3 = new Integer(5);
        private Integer privateInt_3 = new Integer(5);
        protected Integer protectedInt_3 = new Integer(5);
        Integer defaultInt_3 = new Integer(5);
    }

}

TreeTester_1.java

package test.ds;

import com.gcr.structs.annotation.GcRadarToInclude;

public class TreeTester_1
{
    public int publicPrimInt;
    private int privatePrimInt;
    protected int protectedPrimInt;
    int defaultPrimInt;

    @GcRadarToInclude
    public Integer publicInt = new Integer(5);
    private Integer privateInt = new Integer(5);
    protected Integer protectedInt = new Integer(5);
    Integer defaultInt = new Integer(5);
}