/*

 * Copyright (c) 2013, 2014, 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

 * @library /runtime/testlibrary

 * @build GeneratedClassLoader

 * @run main/othervm/timeout=200 -Xmx300m FragmentMetaspace

 */

import java.io.IOException;

/**

 * Test that tries to fragment the native memory used by class loaders.

 * This test creates class loaders that load classes of increasing size for every

 * iteration. By increasing the size of the class meta data needed for every iteration

 * we stress the subsystem for allocating native memory for meta data.

 */

public class FragmentMetaspace {

    public static Class<?> c;

    public static void main(String... args) {

        runGrowing(Long.valueOf(System.getProperty("time", "80000")),

            Integer.valueOf(System.getProperty("iterations", "200")));

        // try to clean up and unload classes to decrease

        // class verification time in debug vm

        System.gc();

    }

    private static void runGrowing(long time, int iterations) {

        long startTime = System.currentTimeMillis();

        for (int i = 0; System.currentTimeMillis() < startTime + time && i < iterations; ++i) {

            try {

                GeneratedClassLoader gcl = new GeneratedClassLoader();

                // getGeneratedClasses throws a RuntimeException in cases where

                // the javac exit code is not 0. If the original reason for the exception is

                // a "java.lang.OutOfMemoryError: Java heap space",

                // increase the heap size in the @run tag and rerun the test.

                // The heap can be exhausted by this test, but heap exhaustion

                // is not a failure mode of this test and should be ignored.

                c = gcl.getGeneratedClasses(i, 100)[0];

                c.newInstance();

                c = null;

                gcl = null;

            } catch (IOException | InstantiationException | IllegalAccessException ex) {

                throw new RuntimeException(ex);

            }

        }

    }

}