jdk-24/test/hotspot/jtreg/runtime/HiddenClasses/GCHiddenClass.java
Harold Seigel e14b026841 8243287: Removal of Unsafe::defineAnonymousClass
Reviewed-by: iklam, mchung, alanb, dholmes
2021-05-13 12:46:54 +00:00

74 lines
2.7 KiB
Java

/*
* Copyright (c) 2020, 2021, 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
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*/
/*
* @test
* @summary Test that hidden classes get garbage collected.
* @library /test/lib
* @modules jdk.compiler
* @run main GCHiddenClass
*/
import java.lang.invoke.MethodType;
import java.lang.invoke.MethodHandles;
import java.lang.invoke.MethodHandles.Lookup;
import java.lang.ref.PhantomReference;
import java.lang.ref.Reference;
import java.lang.ref.ReferenceQueue;
import static java.lang.invoke.MethodHandles.Lookup.ClassOption.*;
import jdk.test.lib.compiler.InMemoryJavaCompiler;
public class GCHiddenClass {
static byte klassbuf[] = InMemoryJavaCompiler.compile("TestClass",
"public class TestClass { " +
" public TestClass() { " +
" System.out.println(\"Hello\"); " +
" } } ");
// A private method is great to keep hidden Class reference local to make it
// GCed on the next cycle
private PhantomReference<Class<?>> createClass(ReferenceQueue<Class<?>> refQueue) throws Exception {
Lookup lookup = MethodHandles.lookup();
Class<?> cl = lookup.defineHiddenClass(klassbuf, false, NESTMATE).lookupClass();
return new PhantomReference<Class<?>>(cl, refQueue);
}
public boolean run() throws Exception {
ReferenceQueue<Class<?>> refQueue = new ReferenceQueue<Class<?>>();
PhantomReference<Class<?>> hiddenClassRef = createClass(refQueue);
System.gc();
Reference<? extends Class<?>> deletedObject = refQueue.remove();
return hiddenClassRef.equals(deletedObject);
}
public static void main(String[] args) throws Throwable {
GCHiddenClass gcHC = new GCHiddenClass();
if (!gcHC.run()) {
throw new RuntimeException("Test failed");
}
}
}