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/*
* Copyright (c) 2018, 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.
*/
/*
* @test
* @bug 8202113
* @summary Test the caller class loader is not kept strongly reachable
* by reflection API
* @library /test/lib/
* @build ReflectionCallerCacheTest Members jdk.test.lib.compiler.CompilerUtils
* @run testng/othervm ReflectionCallerCacheTest
*/
import java.io.IOException;
import java.lang.ref.Cleaner;
import java.lang.ref.WeakReference;
import java.lang.reflect.*;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLClassLoader;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.concurrent.Callable;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.TimeUnit;
import java.util.function.BooleanSupplier;
import jdk.test.lib.compiler.CompilerUtils;
import org.testng.annotations.BeforeTest;
import org.testng.annotations.DataProvider;
import org.testng.annotations.Test;
public class ReflectionCallerCacheTest {
private static final Path CLASSES = Paths.get("classes");
private static final ReflectionCallerCacheTest TEST = new ReflectionCallerCacheTest();
@BeforeTest
public void setup() throws IOException {
String src = System.getProperty("test.src", ".");
String classpath = System.getProperty("test.classes", ".");
boolean rc = CompilerUtils.compile(Paths.get(src, "AccessTest.java"), CLASSES, "-cp", classpath);
if (!rc) {
throw new RuntimeException("fail compilation");
}
}
@DataProvider(name = "memberAccess")
public Object[][] memberAccess() {
return new Object[][] {
{ "AccessTest$PublicConstructor" },
{ "AccessTest$PublicMethod" },
{ "AccessTest$PublicField" },
{ "AccessTest$ProtectedMethod" },
{ "AccessTest$ProtectedField" },
{ "AccessTest$PrivateMethod" },
{ "AccessTest$PrivateField"},
{ "AccessTest$PublicFinalField"},
{ "AccessTest$PrivateFinalField"},
{ "AccessTest$PublicStaticFinalField"},
{ "AccessTest$PrivateStaticFinalField"}
};
}
// Keep the root of the reflective objects strongly reachable
private final Constructor<?> publicConstructor;
private final Method publicMethod;
private final Method protectedMethod;
private final Method privateMethod;
private final Field publicField;
private final Field protectedField;
private final Field privateField;
ReflectionCallerCacheTest() {
try {
this.publicConstructor = Members.class.getConstructor();
this.publicMethod = Members.class.getDeclaredMethod("publicMethod");
this.publicField = Members.class.getDeclaredField("publicField");
this.protectedMethod = Members.class.getDeclaredMethod("protectedMethod");
this.protectedField = Members.class.getDeclaredField("protectedField");
this.privateMethod = Members.class.getDeclaredMethod("privateMethod");
this.privateField = Members.class.getDeclaredField("privateField");
} catch (ReflectiveOperationException e) {
throw new RuntimeException(e);
}
}
@Test(dataProvider = "memberAccess")
private void load(String classname) throws Exception {
WeakReference<?> weakLoader = loadAndRunClass(classname);
// Force garbage collection to trigger unloading of class loader
new ForceGC().await(() -> weakLoader.get() == null);
if (weakLoader.get() != null) {
throw new RuntimeException("Class " + classname + " not unloaded!");
}
}
private WeakReference<?> loadAndRunClass(String classname) throws Exception {
try (TestLoader loader = new TestLoader()) {
// Load member access class with custom class loader
Class<?> c = Class.forName(classname, true, loader);
// access the reflective member
Callable callable = (Callable) c.newInstance();
callable.call();
return new WeakReference<>(loader);
}
}
static class TestLoader extends URLClassLoader {
static URL[] toURLs() {
try {
return new URL[] { CLASSES.toUri().toURL() };
} catch (MalformedURLException e) {
throw new Error(e);
}
}
TestLoader() {
super("testloader", toURLs(), ClassLoader.getSystemClassLoader());
}
}
/**
* Utility class to invoke System.gc()
*/
static class ForceGC {
private final CountDownLatch cleanerInvoked = new CountDownLatch(1);
private final Cleaner cleaner = Cleaner.create();
ForceGC() {
cleaner.register(new Object(), () -> cleanerInvoked.countDown());
}
void doit() {
try {
for (int i = 0; i < 10; i++) {
System.gc();
if (cleanerInvoked.await(1L, TimeUnit.SECONDS)) {
return;
}
}
} catch (InterruptedException unexpected) {
throw new AssertionError("unexpected InterruptedException");
}
}
void await(BooleanSupplier s) {
for (int i = 0; i < 10; i++) {
if (s.getAsBoolean()) return;
doit();
}
throw new AssertionError("failed to satisfy condition");
}
}
}
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