1 /* 2 * Copyright (c) 2016, Oracle 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 /* 25 * @test 26 * @bug 6822627 27 * @summary Test that ReferenceType.constantPool does not produce an NPE 28 * 29 * @author Egor Ushakov 30 * 31 * @modules jdk.jdi/com.sun.tools.jdi:+open 32 * @run build TestScaffold VMConnection 33 * @run compile -g ConstantPoolInfoGC.java 34 * @run main/othervm ConstantPoolInfoGC 35 */ 36 37 import com.sun.jdi.ReferenceType; 38 import com.sun.tools.jdi.ReferenceTypeImpl; 39 40 import java.lang.ref.Reference; 41 import java.lang.reflect.Field; 42 import java.util.Arrays; 43 44 /********** target program **********/ 45 46 class ConstantPoolGCTarg { 47 public static void main(String[] args){ 48 System.out.println("Anything"); 49 } 50 } 51 52 /********** test program **********/ 53 54 public class ConstantPoolInfoGC extends TestScaffold { 55 ReferenceType targetClass; 56 57 ConstantPoolInfoGC(String args[]) { 58 super(args); 59 } 60 61 public static void main(String[] args) throws Exception { 62 new ConstantPoolInfoGC(args).startTests(); 63 } 64 65 /********** test core **********/ 66 67 protected void runTests() throws Exception { 68 targetClass = startToMain("ConstantPoolGCTarg").location().declaringType(); 69 70 if (vm().canGetConstantPool()) { 71 byte[] cpbytes = targetClass.constantPool(); 72 73 // imitate SoftReference cleared 74 Field constantPoolBytesRef = ReferenceTypeImpl.class.getDeclaredField("constantPoolBytesRef"); 75 constantPoolBytesRef.setAccessible(true); 76 Reference softRef = (Reference) constantPoolBytesRef.get(targetClass); 77 softRef.clear(); 78 79 byte[] cpbytes2 = targetClass.constantPool(); 80 if (!Arrays.equals(cpbytes, cpbytes2)) { 81 failure("Consequent constantPool results vary, first was : " + cpbytes + ", now: " + cpbytes2); 82 }; 83 84 } else { 85 System.out.println("can get constant pool version not supported"); 86 } 87 88 89 /* 90 * resume until end 91 */ 92 listenUntilVMDisconnect(); 93 94 /* 95 * deal with results of test 96 * if anything has called failure("foo") testFailed will be true 97 */ 98 if (!testFailed) { 99 println("ConstantPoolInfoGC: passed"); 100 } else { 101 throw new Exception("ConstantPoolInfoGC: failed"); 102 } 103 } 104 }