1 /* 2 * Copyright (c) 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 8140450 27 * @library /test/lib 28 * @summary Test if the getCallerClass method returns empty optional 29 * @run main CallerFromMain exec 30 */ 31 32 import jdk.test.lib.process.ProcessTools; 33 import jdk.test.lib.process.OutputAnalyzer; 34 35 public class CallerFromMain { 36 37 private static final StackWalker sw = StackWalker.getInstance(StackWalker.Option.RETAIN_CLASS_REFERENCE); 38 public static void main(String[] args) throws Exception { 39 if (args.length > 0) { 40 ProcessBuilder pb = ProcessTools.createJavaProcessBuilder(true, "CallerFromMain"); 41 OutputAnalyzer output = ProcessTools.executeProcess(pb); 42 System.out.println(output.getOutput()); 43 output.shouldHaveExitValue(0); 44 return; 45 } 46 47 // StackWalker::getCallerClass 48 // CallerFromMain::main 49 // no caller 50 try { 51 Class<?> c = sw.getCallerClass(); 52 throw new RuntimeException("UOE not thrown. Caller: " + c); 53 } catch (IllegalCallerException e) {} 54 55 // StackWalker::getCallerClass 56 // Runnable::run 57 // Thread::run 58 Thread t1 = new Thread(new Runnable() { 59 @Override 60 public void run() { 61 Class<?> c = sw.getCallerClass(); 62 System.out.println("Call from Thread.run: " + c); 63 assertThreadClassAsCaller(c); 64 } 65 }); 66 t1.setDaemon(true); 67 t1.start(); 68 69 // StackWalker::getCallerClass 70 // CallerFromMain::doit 71 // Thread::run 72 Thread t2 = new Thread(CallerFromMain::doit); 73 t2.setDaemon(true); 74 t2.start(); 75 76 // StackWalker::getCallerClass 77 // MyRunnable::run 78 // Thread::run 79 Thread t3 = new Thread(new MyRunnable()); 80 t3.setDaemon(true); 81 t3.start(); 82 83 // StackWalker::getCallerClass 84 // Runnable::run 85 // MyThread::run 86 Thread t4 = new MyThread(new Runnable() { 87 @Override 88 public void run() { 89 Class<?> c = sw.getCallerClass(); 90 System.out.println("Call from MyThread.run: " + c); 91 if (c != MyThread.class) { 92 throw new RuntimeException("Expected MyThread.class but got " + c); 93 } 94 } 95 }); 96 t4.setDaemon(true); 97 t4.start(); 98 99 t1.join(); 100 t2.join(); 101 t3.join(); 102 t4.join(); 103 } 104 105 static class MyThread extends Thread { 106 final Runnable runnable; 107 MyThread(Runnable runnable) { 108 super("MyThread"); 109 this.runnable = runnable; 110 } 111 public void run() { 112 runnable.run(); 113 } 114 } 115 116 static class MyRunnable implements Runnable { 117 @Override 118 public void run() { 119 Class<?> c = sw.getCallerClass(); 120 System.out.println("Call from Thread::run: " + c); 121 assertThreadClassAsCaller(c); 122 } 123 } 124 125 static void doit() { 126 Class<?> c = sw.getCallerClass(); 127 System.out.println("Call from CallerFromMain.doit: " + c); 128 assertThreadClassAsCaller(c); 129 } 130 131 static void assertThreadClassAsCaller(Class<?> caller) { 132 if (caller != Thread.class) { 133 throw new RuntimeException("Expected Thread.class but got " + caller); 134 } 135 } 136 }