phantom001.java

/*
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
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 * 2 along with this work; if not, write to the Free Software Foundation,
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/*
 * @test
 * @key stress randomness
 *
 * @summary converted from VM Testbase gc/gctests/PhantomReference/phantom001.
 * VM Testbase keywords: [gc, stress, stressopt, nonconcurrent]
 * VM Testbase readme:
 * DESCRIPTION
 *     The test checks that Garbage Collector correctly works with
 *     PhantomReferences. It also checks that no unexpected exceptions and errors
 *     are thrown or the JVM is not crashed.
 *     The test starts a number of threads. Each thread run tests for some time
 *     or serveral iterations.  See javadoc StressOptions for configuration.
 *     First of all each thread defines what type to check (there are 11 types
 *     totally). As soon as the type is defined, a PhantomRefence is created that
 *     refers to an array of tested type and is registered with in a queue. A
 *     PhantomRefence for NonbranchyTree and Referent calsses does not refer to
 *     arrays, but to instances of the classes.
 *     After that a thread performs next checks for the reference:
 *         1. The reference is in queue after GC is provoked with
 *            Algorithms.eatMemory() method (a single thread eats the memory).
 *         2. reference.get() returns null.
 *         3. queue.poll() returns the reference that was created.
 *         4. queue.poll() again returns null.
 *         5. If the checked type is class (Referent), then it must be finalized,
 *            since the reference is already enqueued.
 *         6. reference.clear() does not throw any exception.
 *     The test extends ThreadedGCTest and implements GarbageProducerAware and
 *     MemoryStrategyAware interfaces. The corresponding javadoc documentation
 *     for additional test configuration.
 *
 * @library /vmTestbase
 *          /test/lib
 * @run main/othervm gc.gctests.PhantomReference.phantom001.phantom001 -ms low
 */

package gc.gctests.PhantomReference.phantom001;

import java.lang.ref.*;
import nsk.share.gc.*;
import nsk.share.gc.gp.*;
import nsk.share.gc.gp.string.InternedStringProducer;
import nsk.share.gc.gp.string.RandomStringProducer;

public class phantom001 extends ThreadedGCTest implements GarbageProducerAware, MemoryStrategyAware {

    private GarbageProducer garbageProducer;
    private MemoryStrategy memoryStrategy;
    private InternedStringProducer internedStringProducer = new InternedStringProducer(new RandomStringProducer(10));
    // Total number of types to test
    final static int TYPES_COUNT = 12;
    // Size of array of each tested type. The constant also specifies the
    // number of nodes in a NonbranchyTree and size of each node
    final static int SIZE = 100;

    protected Runnable createRunnable(int i) {
        return new Test();
    }

    public void setGarbageProducer(GarbageProducer garbageProducer) {
        this.garbageProducer = garbageProducer;
    }

    public void setMemoryStrategy(MemoryStrategy memoryStrategy) {
        this.memoryStrategy = memoryStrategy;
    }

    public static void main(String[] args) {
        GC.runTest(new phantom001(), args);
    }

    // The class implements the logic of the testcase
    class Test implements Runnable {

        int iteration;
        private volatile boolean finalized;

        public void run() {
            try {
                log.info("iteration " + iteration);
                ReferenceQueue queue = new ReferenceQueue();
                PhantomReference reference;
                int code = iteration % TYPES_COUNT;
                String type;
                // Define a specific type for each thread to test
                switch (code) {
                    case 0:
                        reference = new PhantomReference(new byte[SIZE], queue);
                        type = "byte";
                        break;
                    case 1:
                        reference = new PhantomReference(new short[SIZE], queue);
                        type = "short";
                        break;
                    case 2:
                        reference = new PhantomReference(new int[SIZE], queue);
                        type = "int";
                        break;
                    case 3:
                        reference = new PhantomReference(new long[SIZE], queue);
                        type = "long";
                        break;
                    case 4:
                        reference = new PhantomReference(new char[SIZE], queue);
                        type = "char";
                        break;
                    case 5:
                        reference = new PhantomReference(new boolean[SIZE], queue);
                        type = "boolean";
                        break;
                    case 6:
                        reference = new PhantomReference(new double[SIZE], queue);
                        type = "double";
                        break;
                    case 7:
                        reference = new PhantomReference(new float[SIZE], queue);
                        type = "float";
                        break;
                    case 8:
                        reference = new PhantomReference(new Object[SIZE], queue);
                        type = "Object";
                        break;
                    case 9:
                        reference = new PhantomReference(new NonbranchyTree(SIZE, 0.3f, SIZE),
                                queue);
                        type = "NonbranchyTree";
                        break;
                    case 10:
                        reference = new PhantomReference(internedStringProducer.create(SIZE), queue);
                        type = "InternedString";
                        break;
                    default:
                        reference = new PhantomReference(new Referent(), queue);
                        type = "class";
                }

                int initialFactor = memoryStrategy.equals(MemoryStrategy.HIGH) ? 1 : (memoryStrategy.equals(MemoryStrategy.LOW) ? 10 : 2);
                GarbageUtils.eatMemory(getExecutionController(), garbageProducer, initialFactor , 10, 0);
                if (type.equals("class")) {
                        while (!finalized && getExecutionController().continueExecution()) {
                                System.runFinalization(); //does not guarantee finalization, but increases the chance
                                try {
                                        Thread.sleep(100);
                                } catch (InterruptedException e) {}
                                GarbageUtils.eatMemory(getExecutionController(), garbageProducer, initialFactor , 10, 0);
                        }

                        //provoke gc once more to make finalized object phantom reachable
                        GarbageUtils.eatMemory(getExecutionController(), garbageProducer, initialFactor , 10, 0);
                }
                if (!getExecutionController().continueExecution()) {
                    // we were interrrupted by stresser. just exit...
                    return;
                }
                Reference polledReference = null;
                try {
                    polledReference = queue.remove();
                } catch (InterruptedException e) {
                    log.error("Unexpected InterruptedException during queue.remove().");
                    setFailed(true);
                }
                // Check the reference and the queue
                // The polled reference must be equal to the one enqueued to
                // the queue

                if (polledReference != reference) {
                    log.error("The original reference is not equal to polled reference.");
                    setFailed(true);
                }

                // queue.poll() once again must return null now, since there is
                // only one reference in the queue
                polledReference = queue.poll();
                if (polledReference != null) {
                    log.error("There are more  than one references in the queue.");
                    setFailed(true);
                }
                reference.clear();
            } catch (OutOfMemoryError e) {
            }
            iteration++;
        }

        class Referent {

                //We need discard this flag to make second and following checks with type.equals("class") useful
                public Referent() {
                                finalized = false;
                        }

                        protected void finalize() {
                finalized = true;
            }
        }
    }

}