/*
 * Copyright (c) 2017, Google 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.
 */

package MyPackage;

/**
 * @test
 * @summary Verifies the JVMTI Heap Monitor Statistics
 * @build Frame
 * @compile HeapMonitorStatTest.java
 * @run main/othervm/native -agentlib:HeapMonitor MyPackage.HeapMonitorStatTest
 */

import java.io.PrintStream;

public class HeapMonitorStatTest {

  static {
    try {
      System.loadLibrary("HeapMonitor");
    } catch (UnsatisfiedLinkError ule) {
      System.err.println("Could not load HeapMonitor library");
      System.err.println("java.library.path: "
          + System.getProperty("java.library.path"));
      throw ule;
    }
  }

  native static int statsNull();
  native static int enableSampling();

  public static int cnt;
  public static int g_tmp[];
  public int array[];

  public static int helper() {
    int sum = 0;
    // Let us assume that the array is 24 bytes of memory.
    for (int i = 0; i < 127000 / 6; i++) {
      int tmp[] = new int[1];
      // Force it to be kept.
      g_tmp = tmp;
      sum += g_tmp[0];
    }
    return sum;
  }

  public static void wrapper() {
    int sum = 0;
    for (int j = 0; j < 1000; j++) {
      sum += helper();
    }
    System.out.println(sum);
  }

  public static void main(String[] args) {

    if (statsNull() == 0) {
      throw new RuntimeException("Statistics should be null to begin with.");
    }

    enableSampling();
    wrapper();

    if (statsNull() != 0) {
      throw new RuntimeException("Statistics should not be null now.");
    }
  }
}