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/*
* Copyright (c) 2020, 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.beans.IntrospectionException;
import java.beans.Introspector;
import java.lang.ref.Reference;
import java.lang.ref.WeakReference;
import java.net.URL;
import java.net.URLClassLoader;
/**
* @test
* @bug 8231454
* @summary Tests cache cleanup by the Introspector.flushXXX()
*/
public final class FlushClassInfoCache {
public static void main(String[] args) throws Exception {
verify(getLoader("testClass"));
verify(getLoader("testAll"));
Reference<ClassLoader> loader = getLoader("test");
// Clear the cache in com.sun.beans.introspect.ClassInfo::CACHE
Introspector.flushCaches();
verify(loader);
}
private static void verify(Reference<?> loader) throws Exception {
int attempt = 0;
while (loader.get() != null) {
if (++attempt > 10) {
throw new RuntimeException("Too many attempts: " + attempt);
}
// Cannot generate OOM here, it will clear the CACHE as well
System.gc();
Thread.sleep(1000);
System.out.println("Not freed :(");
}
}
public static void test() {
try {
Introspector.getBeanInfo(FlushClassInfoCache.class);
} catch (IntrospectionException e) {
throw new RuntimeException(e);
}
}
public static void testClass() {
try {
Introspector.getBeanInfo(FlushClassInfoCache.class);
// Clear the cache in com.sun.beans.introspect.ClassInfo::CACHE
Introspector.flushFromCaches(FlushClassInfoCache.class);
} catch (IntrospectionException e) {
throw new RuntimeException(e);
}
}
public static void testAll() {
try {
Introspector.getBeanInfo(FlushClassInfoCache.class);
// Clear the cache in com.sun.beans.introspect.ClassInfo::CACHE
Introspector.flushCaches();
} catch (IntrospectionException e) {
throw new RuntimeException(e);
}
}
private static Reference<ClassLoader> getLoader(String m) throws Exception {
URL url = FlushClassInfoCache.class.getProtectionDomain()
.getCodeSource().getLocation();
URLClassLoader loader = new URLClassLoader(new URL[]{url}, null);
Class<?> cls = Class.forName("FlushClassInfoCache", true, loader);
cls.getDeclaredMethod(m).invoke(null);
loader.close();
return new WeakReference<>(loader);
}
}
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