/*

 * Copyright (c) 2018, Red Hat, Inc. All rights reserved.

 *

 * 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 TestClassLoaderLeak

 * @summary Test OOME in due to classloader leak

 * @key gc

 * @requires vm.gc.Shenandoah

 * @library /test/lib

 * @run main TestClassLoaderLeak

 */

import java.util.*;

import java.io.*;

import java.nio.*;

import java.nio.file.*;

import jdk.test.lib.process.OutputAnalyzer;

import jdk.test.lib.process.ProcessTools;

public class TestClassLoaderLeak {

    static final int SIZE = 1 * 1024 * 1024;

    static final int COUNT = 128;

    static volatile Object sink;

    static class Dummy {

        static final int[] PAYLOAD = new int[SIZE];

    }

    static class MyClassLoader extends ClassLoader {

        final String path;

        MyClassLoader(String path) {

            this.path = path;

        }

        public Class<?> loadClass(String name) throws ClassNotFoundException {

            try {

                File f = new File(path, name + ".class");

                if (!f.exists()) {

                    return super.loadClass(name);

                }

                Path path = Paths.get(f.getAbsolutePath());

                byte[] cls = Files.readAllBytes(path);

                return defineClass(name, cls, 0, cls.length, null);

            } catch (IOException e) {

                throw new ClassNotFoundException(name);

            }

        }

    }

    static void load(String path) throws Exception {

        ClassLoader cl = new MyClassLoader(path);

        Class<Dummy> c = (Class<Dummy>) Class.forName("TestClassLoaderLeak$Dummy", true, cl);

        if (c.getClassLoader() != cl) {

            throw new IllegalStateException("Should have loaded by target loader");

        }

        sink = c;

    }

    public static void passWith(String... args) throws Exception {

        testWith(true, args);

    }

    public static void failWith(String... args) throws Exception {

        testWith(false, args);

    }

    public static void testWith(boolean shouldPass, String... args) throws Exception {

        List<String> pbArgs = new ArrayList<>();

        pbArgs.add("-Xmx128m");

        pbArgs.add("-XX:+UnlockExperimentalVMOptions");

        pbArgs.add("-XX:+UnlockDiagnosticVMOptions");

        pbArgs.add("-XX:+UseShenandoahGC");

        pbArgs.addAll(Arrays.asList(args));

        pbArgs.add(TestClassLoaderLeak.class.getName());

        pbArgs.add("test");

        ProcessBuilder pb = ProcessTools.createJavaProcessBuilder(pbArgs.toArray(new String[0]));

        OutputAnalyzer analyzer = new OutputAnalyzer(pb.start());

        if (shouldPass) {

            analyzer.shouldHaveExitValue(0);

            analyzer.shouldNotContain("java.lang.OutOfMemoryError");

            analyzer.shouldContain("All good");

        } else {

            analyzer.shouldHaveExitValue(1);

            analyzer.shouldContain("java.lang.OutOfMemoryError");

            analyzer.shouldNotContain("All good");

        }

    }

    public static void main(String[] args) throws Exception {

        if (args.length > 0) {

            String classDir = TestClassLoaderLeak.class.getProtectionDomain().getCodeSource().getLocation().getPath();

            for (int c = 0; c < COUNT; c++) {

                load(classDir);

            }

            System.out.println("All good");

            return;

        }

        String[] heuristics = new String[] {

                "adaptive",

                "compact",

                "static",

                "traversal",

                "aggressive",

                "passive",

        };

        for (String h : heuristics) {

            // Forceful enabling should work

            passWith("-XX:ShenandoahGCHeuristics=" + h, "-XX:+ClassUnloading");

            passWith("-XX:ShenandoahGCHeuristics=" + h, "-XX:+ClassUnloadingWithConcurrentMark");

            // Even when concurrent unloading is disabled, Full GC has to recover

            passWith("-XX:ShenandoahGCHeuristics=" + h, "-XX:+ClassUnloading", "-XX:-ClassUnloadingWithConcurrentMark");

            passWith("-XX:ShenandoahGCHeuristics=" + h, "-XX:+ClassUnloading", "-XX:-ClassUnloadingWithConcurrentMark", "-XX:ShenandoahUnloadClassesFrequency=0");

            passWith("-XX:ShenandoahGCHeuristics=" + h, "-XX:+ClassUnloading", "-XX:+ClassUnloadingWithConcurrentMark", "-XX:ShenandoahUnloadClassesFrequency=0");

            // Should OOME when unloading forcefully disabled, even if local flags try to enable it back

            failWith("-XX:ShenandoahGCHeuristics=" + h, "-XX:-ClassUnloading");

            failWith("-XX:ShenandoahGCHeuristics=" + h, "-XX:-ClassUnloading", "-XX:+ClassUnloadingWithConcurrentMark");

            failWith("-XX:ShenandoahGCHeuristics=" + h, "-XX:-ClassUnloading", "-XX:+ClassUnloadingWithConcurrentMark", "-XX:ShenandoahUnloadClassesFrequency=1");

            failWith("-XX:ShenandoahGCHeuristics=" + h, "-XX:-ClassUnloading", "-XX:-ClassUnloadingWithConcurrentMark", "-XX:ShenandoahUnloadClassesFrequency=1");

        }

    }

}