/*

* Copyright (c) 2013, 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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import sun.management.ManagementFactoryHelper;

import com.sun.management.HotSpotDiagnosticMXBean;

import com.sun.management.VMOption;

import java.util.regex.Matcher;

import java.util.regex.Pattern;

import java.util.ArrayList;

import java.util.Arrays;

import com.oracle.java.testlibrary.*;

import sun.hotspot.WhiteBox;

class DetermineMaxHeapForCompressedOops {

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

    WhiteBox wb = WhiteBox.getWhiteBox();

    System.out.print(wb.getCompressedOopsMaxHeapSize());

  }

}

class TestUseCompressedOopsErgoTools {

  private static long getClassMetaspaceSize() {

    HotSpotDiagnosticMXBean diagnostic = ManagementFactoryHelper.getDiagnosticMXBean();

    VMOption option = diagnostic.getVMOption("ClassMetaspaceSize");

    return Long.parseLong(option.getValue());

  }

  public static long getMaxHeapForCompressedOops(String[] vmargs) throws Exception {

    OutputAnalyzer output = runWhiteBoxTest(vmargs, DetermineMaxHeapForCompressedOops.class.getName(), new String[] {}, false);

    return Long.parseLong(output.getStdout());

  }

  public static boolean is64bitVM() {

    String val = System.getProperty("sun.arch.data.model");

    if (val == null) {

      throw new RuntimeException("Could not read sun.arch.data.model");

    }

    if (val.equals("64")) {

      return true;

    } else if (val.equals("32")) {

      return false;

    }

    throw new RuntimeException("Unexpected value " + val + " of sun.arch.data.model");

  }

  /**

   * Executes a new VM process with the given class and parameters.

   * @param vmargs Arguments to the VM to run

   * @param classname Name of the class to run

   * @param arguments Arguments to the class

   * @param useTestDotJavaDotOpts Use test.java.opts as part of the VM argument string

   * @return The OutputAnalyzer with the results for the invocation.

   */

  public static OutputAnalyzer runWhiteBoxTest(String[] vmargs, String classname, String[] arguments, boolean useTestDotJavaDotOpts) throws Exception {

    ArrayList<String> finalargs = new ArrayList<String>();

    String[] whiteboxOpts = new String[] {

      "-Xbootclasspath/a:.",

      "-XX:+UnlockDiagnosticVMOptions", "-XX:+WhiteBoxAPI",

      "-cp", System.getProperty("java.class.path"),

    };

    if (useTestDotJavaDotOpts) {

      // System.getProperty("test.java.opts") is '' if no options is set,

      // we need to skip such a result

      String[] externalVMOpts = new String[0];

      if (System.getProperty("test.java.opts") != null && System.getProperty("test.java.opts").length() != 0) {

        externalVMOpts = System.getProperty("test.java.opts").split(" ");

      }

      finalargs.addAll(Arrays.asList(externalVMOpts));

    }

    finalargs.addAll(Arrays.asList(vmargs));

    finalargs.addAll(Arrays.asList(whiteboxOpts));

    finalargs.add(classname);

    finalargs.addAll(Arrays.asList(arguments));

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

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

    output.shouldHaveExitValue(0);

    return output;

  }

  private static String[] join(String[] part1, String part2) {

    ArrayList<String> result = new ArrayList<String>();

    result.addAll(Arrays.asList(part1));

    result.add(part2);

    return result.toArray(new String[0]);

  }

  public static void checkCompressedOopsErgo(String[] gcflags) throws Exception {

    long maxHeapForCompressedOops = getMaxHeapForCompressedOops(gcflags);

    checkUseCompressedOops(gcflags, maxHeapForCompressedOops, true);

    checkUseCompressedOops(gcflags, maxHeapForCompressedOops - 1, true);

    checkUseCompressedOops(gcflags, maxHeapForCompressedOops + 1, false);

    // the use of HeapBaseMinAddress should not change the outcome

    checkUseCompressedOops(join(gcflags, "-XX:HeapBaseMinAddress=32G"), maxHeapForCompressedOops, true);

    checkUseCompressedOops(join(gcflags, "-XX:HeapBaseMinAddress=32G"), maxHeapForCompressedOops - 1, true);

    checkUseCompressedOops(join(gcflags, "-XX:HeapBaseMinAddress=32G"), maxHeapForCompressedOops + 1, false);

    // use a different object alignment

    maxHeapForCompressedOops = getMaxHeapForCompressedOops(join(gcflags, "-XX:ObjectAlignmentInBytes=16"));

    checkUseCompressedOops(join(gcflags, "-XX:ObjectAlignmentInBytes=16"), maxHeapForCompressedOops, true);

    checkUseCompressedOops(join(gcflags, "-XX:ObjectAlignmentInBytes=16"), maxHeapForCompressedOops - 1, true);

    checkUseCompressedOops(join(gcflags, "-XX:ObjectAlignmentInBytes=16"), maxHeapForCompressedOops + 1, false);

    // use a different ClassMetaspaceSize

    String classMetaspaceSizeArg = "-XX:ClassMetaspaceSize=" + 2 * getClassMetaspaceSize();

    maxHeapForCompressedOops = getMaxHeapForCompressedOops(join(gcflags, classMetaspaceSizeArg));

    checkUseCompressedOops(join(gcflags, classMetaspaceSizeArg), maxHeapForCompressedOops, true);

    checkUseCompressedOops(join(gcflags, classMetaspaceSizeArg), maxHeapForCompressedOops - 1, true);

    checkUseCompressedOops(join(gcflags, classMetaspaceSizeArg), maxHeapForCompressedOops + 1, false);

  }

  private static void checkUseCompressedOops(String[] args, long heapsize, boolean expectUseCompressedOops) throws Exception {

     ArrayList<String> finalargs = new ArrayList<String>();

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

     finalargs.add("-Xmx" + heapsize);

     finalargs.add("-XX:+PrintFlagsFinal");

     finalargs.add("-version");

     String output = expectValid(finalargs.toArray(new String[0]));

     boolean actualUseCompressedOops = getFlagBoolValue(" UseCompressedOops", output);

     if (expectUseCompressedOops != actualUseCompressedOops) {

       throw new RuntimeException("Expected use of compressed oops: " + expectUseCompressedOops + " but was: " + actualUseCompressedOops);

     }

  }

  private static boolean getFlagBoolValue(String flag, String where) {

    Matcher m = Pattern.compile(flag + "\\s+:?= (true|false)").matcher(where);

    if (!m.find()) {

      throw new RuntimeException("Could not find value for flag " + flag + " in output string");

    }

    String match = m.group(1).equals("true");

  }

  private static String expect(String[] flags, boolean hasWarning, boolean hasError, int errorcode) throws Exception {

    ProcessBuilder pb = ProcessTools.createJavaProcessBuilder(flags);

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

    output.shouldHaveExitValue(errorcode);

    return output.getStdout();

  }

  private static String expectValid(String[] flags) throws Exception {

    return expect(flags, false, false, 0);

  }

}