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/*
* 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 8140450
* @library /lib/testlibrary
* @build jdk.testlibrary.*
* @summary Test if the getCallerClass method returns empty optional
* @run main CallerFromMain exec
*/
import jdk.testlibrary.ProcessTools;
import jdk.testlibrary.OutputAnalyzer;
public class CallerFromMain {
private static final StackWalker sw = StackWalker.getInstance(StackWalker.Option.RETAIN_CLASS_REFERENCE);
public static void main(String[] args) throws Exception {
if (args.length > 0) {
ProcessBuilder pb = ProcessTools.createJavaProcessBuilder(true, "CallerFromMain");
OutputAnalyzer output = ProcessTools.executeProcess(pb);
System.out.println(output.getOutput());
output.shouldHaveExitValue(0);
return;
}
// StackWalker::getCallerClass
// CallerFromMain::main
// no caller
try {
Class<?> c = sw.getCallerClass();
throw new RuntimeException("UOE not thrown. Caller: " + c);
} catch (IllegalCallerException e) {}
// StackWalker::getCallerClass
// Runnable::run
// Thread::run
Thread t1 = new Thread(new Runnable() {
@Override
public void run() {
Class<?> c = sw.getCallerClass();
System.out.println("Call from Thread.run: " + c);
assertThreadClassAsCaller(c);
}
});
t1.setDaemon(true);
t1.start();
// StackWalker::getCallerClass
// CallerFromMain::doit
// Thread::run
Thread t2 = new Thread(CallerFromMain::doit);
t2.setDaemon(true);
t2.start();
// StackWalker::getCallerClass
// MyRunnable::run
// Thread::run
Thread t3 = new Thread(new MyRunnable());
t3.setDaemon(true);
t3.start();
// StackWalker::getCallerClass
// Runnable::run
// MyThread::run
Thread t4 = new MyThread(new Runnable() {
@Override
public void run() {
Class<?> c = sw.getCallerClass();
System.out.println("Call from MyThread.run: " + c);
if (c != MyThread.class) {
throw new RuntimeException("Expected MyThread.class but got " + c);
}
}
});
t4.setDaemon(true);
t4.start();
t1.join();
t2.join();
t3.join();
t4.join();
}
static class MyThread extends Thread {
final Runnable runnable;
MyThread(Runnable runnable) {
super("MyThread");
this.runnable = runnable;
}
public void run() {
runnable.run();
}
}
static class MyRunnable implements Runnable {
@Override
public void run() {
Class<?> c = sw.getCallerClass();
System.out.println("Call from Thread::run: " + c);
assertThreadClassAsCaller(c);
}
}
static void doit() {
Class<?> c = sw.getCallerClass();
System.out.println("Call from CallerFromMain.doit: " + c);
assertThreadClassAsCaller(c);
}
static void assertThreadClassAsCaller(Class<?> caller) {
if (caller != Thread.class) {
throw new RuntimeException("Expected Thread.class but got " + caller);
}
}
}
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