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/*
* Copyright (c) 2010, 2016, 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.
*
* 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.
*/
import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import static jdk.testlibrary.Asserts.assertGreaterThan;
import jdk.testlibrary.ProcessTools;
import com.sun.tools.attach.AttachNotSupportedException;
import com.sun.tools.attach.VirtualMachine;
import sun.tools.attach.HotSpotVirtualMachine;
/*
* @test
* @bug 6942989
* @summary Check for WeakReference leak in Logger and anonymous Logger objects
* @library /lib/testlibrary
* @modules jdk.attach/sun.tools.attach
* java.logging
* @build jdk.testlibrary.ProcessTools
* @run main/othervm -Djdk.attach.allowAttachSelf TestLoggerWeakRefLeak Logger
* @run main/othervm -Djdk.attach.allowAttachSelf TestLoggerWeakRefLeak AnonymousLogger
*/
public class TestLoggerWeakRefLeak {
private static final String TARGET_CLASS = "java.lang.ref.WeakReference";
private static final int INSTANCE_COUNT = 100;
private static int loggerCount = 0;
public static void main(String[] args) throws Exception {
if (args[0].equals("AnonymousLogger")) {
System.out.println("Test for WeakReference leak in AnonymousLogger object");
testIfLeaking(TestLoggerWeakRefLeak::callAnonymousLogger);
} else {
System.out.println("Test for WeakReference leak in Logger object");
testIfLeaking(TestLoggerWeakRefLeak::callLogger);
}
}
/**
* For these particular WeakReference leaks, the count was always observed
* to be increasing so if decreasing or the same count is observed,
* then there is no leak.
*/
private static void testIfLeaking(Runnable callLogger) throws Exception {
long count = 0;
int instanceCount = 0;
int previousInstanceCount = 0;
int increasingCount = 0;
int decreasingCount = 0;
while (true) {
callLogger.run();
count += INSTANCE_COUNT;
if ((count % 1000) == 0) {
System.out.println("call count = " + count);
instanceCount = getInstanceCountFromHeapHisto();
if (instanceCount > previousInstanceCount) {
increasingCount++;
} else {
decreasingCount++;
System.out.println("increasing count: " + increasingCount);
System.out.println("decreasing or the same count: " + decreasingCount);
System.out.println("Test passed: decreasing or the same instance count is observed");
break;
}
previousInstanceCount = instanceCount;
}
delayExecution();
}
}
/**
* This Logger call is leaking two different WeakReferences:
* - one in LogManager.LogNode
* - one in Logger.kids
*/
private static void callLogger() {
for (int i = 0; i < INSTANCE_COUNT; i++) {
java.util.logging.Logger.getLogger("logger-" + loggerCount);
if (++loggerCount >= 25000) {
// Limit the Logger namespace used by the test so the weak refs
// in LogManager.loggers that are being properly managed
// don't skew the counts by too much.
loggerCount = 0;
}
}
}
/**
* This Logger call is leaking a WeakReference in Logger.kids
*/
private static void callAnonymousLogger() {
for (int i = 0; i < INSTANCE_COUNT; i++) {
java.util.logging.Logger.getAnonymousLogger();
}
}
/**
* 'vm.heapHisto("-live")' will request a full GC
*/
private static int getInstanceCountFromHeapHisto() throws AttachNotSupportedException, Exception {
int instanceCount = 0;
HotSpotVirtualMachine vm = (HotSpotVirtualMachine) VirtualMachine
.attach(Long.toString(ProcessTools.getProcessId()));
try {
try (InputStream heapHistoStream = vm.heapHisto("-live");
BufferedReader in = new BufferedReader(new InputStreamReader(heapHistoStream))) {
String inputLine;
while ((inputLine = in.readLine()) != null) {
if (inputLine.contains(TARGET_CLASS)) {
instanceCount = Integer.parseInt(inputLine
.split("[ ]+")[2]);
System.out.println("instance count: " + instanceCount);
break;
}
}
}
} finally {
vm.detach();
}
assertGreaterThan(instanceCount, 0, "No instances of " + TARGET_CLASS + " are found");
return instanceCount;
}
/**
* Delay for 1/10 of a second to avoid CPU saturation
*/
private static void delayExecution() {
try {
Thread.sleep(100);
} catch (InterruptedException ie) {
// Ignore any exceptions
}
}
}
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