2023-11-02 16:38:30 +00:00

90 lines
3.6 KiB
Java

/*
* Copyright (c) 2021, 2023, Oracle and/or its affiliates. All rights reserved.
* Copyright (c) 2021, BELLSOFT. 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.
*/
/*
* LoadLibraryDeadlock class triggers the deadlock between the two
* lock objects - ZipFile object and ClassLoader.loadedLibraryNames hashmap.
* Thread #2 loads a signed jar which leads to acquiring the lock objects in
* natural order (ZipFile then HashMap) - loading a signed jar may involve
* Providers initialization. Providers may load native libraries.
* Thread #1 acquires the locks in reverse order, first entering loadLibrary
* called from Class1, then acquiring ZipFile during the search for a class
* triggered from JNI.
*/
import java.lang.*;
import java.net.URISyntaxException;
public class LoadLibraryDeadlock {
public static void main(String[] args) {
System.out.println("LoadLibraryDeadlock test started");
Thread t1 = new Thread() {
public void run() {
try {
// an instance of unsigned class that loads a native library
Class<?> c1 = Class.forName("Class1");
Object o = c1.newInstance();
System.out.println("Class1 loaded from " + getLocation(c1));
} catch (ClassNotFoundException |
InstantiationException |
IllegalAccessException e) {
System.out.println("Class Class1 not found.");
throw new RuntimeException(e);
}
}
};
Thread t2 = new Thread() {
public void run() {
try {
// load a class from a signed jar, which locks the JarFile
Class<?> c2 = Class.forName("p.Class2");
System.out.println("Class2 loaded from " + getLocation(c2));
} catch (ClassNotFoundException e) {
System.out.println("Class Class2 not found.");
throw new RuntimeException(e);
}
}
};
t2.start();
t1.start();
try {
t1.join();
t2.join();
} catch (InterruptedException ex) {
throw new RuntimeException(ex);
}
}
private static String getLocation(Class<?> c) {
var pd = c.getProtectionDomain();
var cs = pd != null ? pd.getCodeSource() : null;
try {
// same format as returned by TestLoadLibraryDeadlock::getLocation
return cs != null ? cs.getLocation().toURI().getPath() : null;
} catch (URISyntaxException ex) {
throw new RuntimeException(ex);
}
}
}