1 /* 2 * Copyright (c) 2017, Google and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 */ 23 24 package MyPackage; 25 26 /** 27 * @test 28 * @summary Verifies the JVMTI Heap Monitor Statistics 29 * @compile HeapMonitorStatSimpleTest.java 30 * @run main/othervm/native -agentlib:HeapMonitor MyPackage.HeapMonitorStatSimpleTest 31 */ 32 33 public class HeapMonitorStatSimpleTest { 34 35 static { 36 try { 37 System.loadLibrary("HeapMonitor"); 38 } catch (UnsatisfiedLinkError ule) { 39 System.err.println("Could not load HeapMonitor library"); 40 System.err.println("java.library.path: " 41 + System.getProperty("java.library.path")); 42 throw ule; 43 } 44 } 45 46 private static int g_tmp[]; 47 48 private native static int statsNull(); 49 private native static int enableSampling(); 50 51 private static int helper() { 52 int sum = 0; 53 // Let us assume that the array is 24 bytes of memory. 54 for (int i = 0; i < 127000 / 6; i++) { 55 int tmp[] = new int[1]; 56 // Force it to be kept. 57 g_tmp = tmp; 58 sum += g_tmp[0]; 59 } 60 return sum; 61 } 62 63 private static void wrapper() { 64 int sum = 0; 65 for (int j = 0; j < 1000; j++) { 66 sum += helper(); 67 } 68 System.out.println(sum); 69 } 70 71 public static void main(String[] args) { 72 if (statsNull() == 0) { 73 throw new RuntimeException("Statistics should be null to begin with."); 74 } 75 76 enableSampling(); 77 wrapper(); 78 79 if (statsNull() != 0) { 80 throw new RuntimeException("Statistics should not be null now."); 81 } 82 } 83 }