Examples with Reference java.lang.ref.Reference used on opensource projects

Example 1 with Reference

use of java.lang.ref.Reference in project ACS by ACS-Community.

the class GarbageCollectionTestHelper method waitForGC.

/**
     * a simple algorithm to wait for GC
     */
public boolean waitForGC(long maxTimeout) {
    long startTime = System.currentTimeMillis();
    long timeOut = maxTimeout;
    Reference retRef = null;
    System.gc();
    while (true) {
        try {
            retRef = refQ.remove(timeOut);
            break;
        } catch (InterruptedException ex) {
            long delta = System.currentTimeMillis() - startTime;
            if (delta < maxTimeout) {
                timeOut = maxTimeout - delta;
                continue;
            }
        }
    // catch
    }
    return (retRef != null);
}

Example 2 with Reference

use of java.lang.ref.Reference in project ACS by ACS-Community.

the class GarbageCollectionTestHelper method complexWaitForGC.

/**
     * a more sophisticated algorithm to wait for Property Change Events
     */
public boolean complexWaitForGC(long maxTimeout) {
    long startTime = System.currentTimeMillis();
    long timeOut = maxTimeout;
    Reference retRef = null;
    int slices = (int) (maxTimeout / GC_SLICE_MILLIS);
    //@
    System.err.println("waiting for " + slices + " slices");
    for (int ix = 0; ix < slices; ix++) {
        System.gc();
        //@
        System.err.println("sleeping for " + GC_SLICE_MILLIS);
        try {
            Thread.currentThread().sleep(GC_SLICE_MILLIS);
        } catch (InterruptedException ex) {
            ex.printStackTrace();
        }
        retRef = refQ.poll();
        if (retRef != null) {
            return true;
        }
    }
    return (retRef != null);
}

Example 3 with Reference

use of java.lang.ref.Reference in project jdk8u_jdk by JetBrains.

the class ConstantPoolInfoGC method runTests.

/********** test core **********/
protected void runTests() throws Exception {
    targetClass = startToMain("ConstantPoolGCTarg").location().declaringType();
    if (vm().canGetConstantPool()) {
        byte[] cpbytes = targetClass.constantPool();
        // imitate SoftReference cleared
        Field constantPoolBytesRef = ReferenceTypeImpl.class.getDeclaredField("constantPoolBytesRef");
        constantPoolBytesRef.setAccessible(true);
        Reference softRef = (Reference) constantPoolBytesRef.get(targetClass);
        softRef.clear();
        byte[] cpbytes2 = targetClass.constantPool();
        if (!Arrays.equals(cpbytes, cpbytes2)) {
            failure("Consequent constantPool results vary, first was : " + cpbytes + ", now: " + cpbytes2);
        }
        ;
    } else {
        System.out.println("can get constant pool version not supported");
    }
    /*
         * resume until end
         */
    listenUntilVMDisconnect();
    /*
         * deal with results of test
         * if anything has called failure("foo") testFailed will be true
         */
    if (!testFailed) {
        println("ConstantPoolInfoGC: passed");
    } else {
        throw new Exception("ConstantPoolInfoGC: failed");
    }
}

Example 4 with Reference

use of java.lang.ref.Reference in project jdk8u_jdk by JetBrains.

the class RuntimeThreadInheritanceLeak method main.

public static void main(String[] args) {
    System.err.println("\nRegression test for bug 4404702\n");
    /*
         * HACK: Work around the fact that java.util.logging.LogManager's
         * (singleton) construction also has this bug-- it will register a
         * "shutdown hook", i.e. a thread, which will inherit and pin the
         * current thread's context class loader for the lifetime of the VM--
         * by causing the LogManager to be initialized now, instead of by
         * RMI when our special context class loader is set.
         */
    java.util.logging.LogManager.getLogManager();
    /*
         * HACK: Work around the fact that the non-native, thread-based
         * SecureRandom seed generator (ThreadedSeedGenerator) seems to
         * have this bug too (which had been causing this test to fail
         * when run with jtreg on Windows XP-- see 4910382).
         */
    (new java.security.SecureRandom()).nextInt();
    RuntimeThreadInheritanceLeak obj = new RuntimeThreadInheritanceLeak();
    try {
        ClassLoader loader = URLClassLoader.newInstance(new URL[0]);
        ReferenceQueue refQueue = new ReferenceQueue();
        Reference loaderRef = new WeakReference(loader, refQueue);
        System.err.println("created loader: " + loader);
        Thread.currentThread().setContextClassLoader(loader);
        UnicastRemoteObject.exportObject(obj);
        Thread.currentThread().setContextClassLoader(ClassLoader.getSystemClassLoader());
        System.err.println("exported remote object with loader as context class loader");
        loader = null;
        System.err.println("nulled strong reference to loader");
        UnicastRemoteObject.unexportObject(obj, true);
        System.err.println("unexported remote object");
        /*
             * HACK: Work around the fact that the sun.misc.GC daemon thread
             * also has this bug-- it will have inherited our loader as its
             * context class loader-- by giving it a chance to pass away.
             */
        Thread.sleep(2000);
        System.gc();
        System.err.println("waiting to be notified of loader being weakly reachable...");
        Reference dequeued = refQueue.remove(TIMEOUT);
        if (dequeued == null) {
            System.err.println("TEST FAILED: loader not deteced weakly reachable");
            dumpThreads();
            throw new RuntimeException("TEST FAILED: loader not detected weakly reachable");
        }
        System.err.println("TEST PASSED: loader detected weakly reachable");
        dumpThreads();
    } catch (RuntimeException e) {
        throw e;
    } catch (Exception e) {
        throw new RuntimeException("TEST FAILED: unexpected exception", e);
    } finally {
        try {
            UnicastRemoteObject.unexportObject(obj, true);
        } catch (RemoteException e) {
        }
    }
}

Example 5 with Reference

use of java.lang.ref.Reference in project jdk8u_jdk by JetBrains.

the class JpegWriterLeakTest method main.

public static void main(String[] args) {
    final ReferenceQueue<ImageWriter> queue = new ReferenceQueue<>();
    final ArrayList<Reference<? extends ImageWriter>> refs = new ArrayList<>();
    int count = 2;
    do {
        ImageWriter writer = ImageIO.getImageWritersByFormatName("jpeg").next();
        final WeakReference<? extends ImageWriter> ref = new WeakReference<>(writer, queue);
        refs.add(ref);
        try {
            final ImageOutputStream os = ImageIO.createImageOutputStream(new ByteArrayOutputStream());
            writer.setOutput(os);
            writer.write(getImage());
        // NB: dispose() or reset() workarounds the problem.
        } catch (IOException e) {
        } finally {
            writer = null;
        }
        count--;
    } while (count > 0);
    System.out.println("Wait for GC...");
    final long testTimeOut = 60000L;
    final long startTime = System.currentTimeMillis();
    while (!refs.isEmpty()) {
        // check for the test timeout
        final long now = System.currentTimeMillis();
        if (now - startTime > testTimeOut) {
            System.out.println();
            throw new RuntimeException("Test FAILED.");
        }
        System.gc();
        try {
            System.out.print(".");
            Thread.sleep(1000);
        } catch (InterruptedException e) {
        }
        ;
        Reference<? extends ImageWriter> r = queue.poll();
        if (r != null) {
            System.out.println("Got reference: " + r);
            refs.remove(r);
        }
    }
    System.out.println("Test PASSED.");
}