1 /* 2 * Copyright (c) 2013, 2015, 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 8021897 27 * @summary Test getting the value for an uninitialized String object 28 * @author Staffan Larsen 29 * 30 * @run build TestScaffold VMConnection TargetListener TargetAdapter 31 * @run compile -g GetUninitializedStringValue.java 32 * @run driver GetUninitializedStringValue 33 */ 34 import com.sun.jdi.ReferenceType; 35 import com.sun.jdi.StackFrame; 36 import com.sun.jdi.StringReference; 37 import com.sun.jdi.ThreadReference; 38 import com.sun.jdi.event.BreakpointEvent; 39 40 /********** target program **********/ 41 42 class GetUninitializedStringValueTarg { 43 public static void main(String[] args) { 44 new String("foo"); 45 System.out.println("Goodbye from GetUninitializedStringValueTarg!"); 46 } 47 } 48 49 /********** test program **********/ 50 51 public class GetUninitializedStringValue extends TestScaffold { 52 ReferenceType targetClass; 53 ThreadReference mainThread; 54 55 GetUninitializedStringValue (String args[]) { 56 super(args); 57 } 58 59 public static void main(String[] args) 60 throws Exception 61 { 62 new GetUninitializedStringValue (args).startTests(); 63 } 64 65 /********** test core **********/ 66 67 protected void runTests() 68 throws Exception 69 { 70 /* 71 * Run to String.<init> 72 */ 73 startUp("GetUninitializedStringValueTarg"); 74 BreakpointEvent bpe = resumeTo("java.lang.String", "<init>", "(Ljava/lang/String;)V"); 75 76 /* 77 * We've arrived. Look at 'this' - it will be uninitialized (the value field will not be set yet). 78 */ 79 StackFrame frame = bpe.thread().frame(0); 80 StringReference sr = (StringReference)frame.thisObject(); 81 if (!sr.value().equals("")) { 82 throw new Exception("Unexpected value for the uninitialized String"); 83 } 84 85 /* 86 * resume the target listening for events 87 */ 88 listenUntilVMDisconnect(); 89 } 90 }