| /* |
| * Copyright (c) 2015, 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 |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| /* |
| * @test |
| * @bug 8020968 |
| * @summary Sanity test for locals and operands |
| * @run main LocalsAndOperands |
| */ |
| |
| import java.lang.StackWalker.StackFrame; |
| import java.lang.reflect.*; |
| import java.util.List; |
| import java.util.stream.Collectors; |
| |
| public class LocalsAndOperands { |
| static Class<?> liveStackFrameClass; |
| static Class<?> primitiveValueClass; |
| static StackWalker extendedWalker; |
| static Method getLocals; |
| static Method getOperands; |
| static Method getMonitors; |
| static Method primitiveType; |
| public static void main(String... args) throws Exception { |
| liveStackFrameClass = Class.forName("java.lang.LiveStackFrame"); |
| primitiveValueClass = Class.forName("java.lang.LiveStackFrame$PrimitiveValue"); |
| |
| getLocals = liveStackFrameClass.getDeclaredMethod("getLocals"); |
| getLocals.setAccessible(true); |
| |
| getOperands = liveStackFrameClass.getDeclaredMethod("getStack"); |
| getOperands.setAccessible(true); |
| |
| getMonitors = liveStackFrameClass.getDeclaredMethod("getMonitors"); |
| getMonitors.setAccessible(true); |
| |
| primitiveType = primitiveValueClass.getDeclaredMethod("type"); |
| primitiveType.setAccessible(true); |
| |
| Method method = liveStackFrameClass.getMethod("getStackWalker"); |
| method.setAccessible(true); |
| extendedWalker = (StackWalker) method.invoke(null); |
| new LocalsAndOperands(extendedWalker, true).test(); |
| |
| // no access to local and operands. |
| new LocalsAndOperands(StackWalker.getInstance(), false).test(); |
| } |
| |
| private final StackWalker walker; |
| private final boolean extended; |
| LocalsAndOperands(StackWalker walker, boolean extended) { |
| this.walker = walker; |
| this.extended = extended; |
| } |
| |
| synchronized void test() throws Exception { |
| int x = 10; |
| char c = 'z'; |
| String hi = "himom"; |
| long l = 1000000L; |
| double d = 3.1415926; |
| |
| List<StackWalker.StackFrame> frames = walker.walk(s -> s.collect(Collectors.toList())); |
| if (extended) { |
| for (StackWalker.StackFrame f : frames) { |
| System.out.println("frame: " + f); |
| Object[] locals = (Object[]) getLocals.invoke(f); |
| for (int i = 0; i < locals.length; i++) { |
| System.out.format(" local %d: %s type %s\n", i, locals[i], type(locals[i])); |
| |
| // check for non-null locals in LocalsAndOperands.test() |
| if (f.getClassName().equals("LocalsAndOperands") && |
| f.getMethodName().equals("test")) { |
| if (locals[i] == null) { |
| throw new RuntimeException("kept-alive locals should not be null"); |
| } |
| } |
| } |
| |
| Object[] operands = (Object[]) getOperands.invoke(f); |
| for (int i = 0; i < operands.length; i++) { |
| System.out.format(" operand %d: %s type %s%n", i, operands[i], |
| type(operands[i])); |
| } |
| |
| Object[] monitors = (Object[]) getMonitors.invoke(f); |
| for (int i = 0; i < monitors.length; i++) { |
| System.out.format(" monitor %d: %s%n", i, monitors[i]); |
| } |
| } |
| } else { |
| for (StackFrame f : frames) { |
| if (liveStackFrameClass.isInstance(f)) { |
| throw new RuntimeException("should not be LiveStackFrame"); |
| } |
| } |
| } |
| // Use local variables so they stay alive |
| System.out.println("Stayin' alive: "+x+" "+c+" "+hi+" "+l+" "+d); |
| } |
| |
| String type(Object o) throws Exception { |
| if (o == null) { |
| return "null"; |
| } else if (primitiveValueClass.isInstance(o)) { |
| char c = (char)primitiveType.invoke(o); |
| return String.valueOf(c); |
| } else { |
| return o.getClass().getName(); |
| } |
| } |
| } |