--- /dev/null 2018-11-15 14:54:37.349029000 +0000 +++ new/test/jdk/java/net/URL/RacyHandler.java 2018-11-21 12:57:40.826447781 +0000 @@ -0,0 +1,113 @@ +/* + * Copyright (c) 2018, 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. + */ + +import java.io.IOException; +import java.lang.reflect.*; +import java.net.URL; +import java.net.URLConnection; +import java.net.URLStreamHandler; +import java.util.concurrent.CountDownLatch; + +/* + * @test + * @bug 8213942 + * @summary URLStreamHandler initialization race + * @run main/othervm RacyHandler + * @run main/othervm RacyHandler + * @run main/othervm RacyHandler + */ + +/* + * This test makes reasonable effort to reproduce the race. + * Run repeatedly to ensure correctness. + */ +public class RacyHandler { + static volatile boolean factorySet = false; + static int NUM_THREADS = 2; + static CountDownLatch cdl = new CountDownLatch(NUM_THREADS + 1); + + public static void main(String[] args) { + RacyHandler tester = new RacyHandler(); + tester.runTest(); + } + + public void runTest() { + new Thread(() -> { + try { + cdl.await(); + URL.setURLStreamHandlerFactory(proto -> new CustomHttpHandler()); + factorySet = true; + } catch (Exception ignore) { } + }).start(); + cdl.countDown(); + + for (int i = 0; i < NUM_THREADS; i++) { + new Thread(() -> { + try { + cdl.await(); + while (!factorySet) { + // trigger URL class load + getURLStreamHandler(); + } + } catch (Exception ignore) { } + }).start(); + cdl.countDown(); + } + + // wait for the factory to be set + while (!factorySet) { } + // The sleep seems to help trigger the failure + try { + Thread.sleep(500); + } catch (InterruptedException ie) { + } + + URLStreamHandler httpHandler = getURLStreamHandler(); + System.out.println("After setting factory URL handlers: http " + httpHandler); + if (!(httpHandler instanceof CustomHttpHandler)) + throw new RuntimeException("FAILED: Incorrect handler type"); + } + + /* + * This is just so we can see what we get for the URLStreamHandler back + * from the factory to verify whether it really is using our Handler + * or something else... + */ + public URLStreamHandler getURLStreamHandler() { + try { + Method method = URL.class.getDeclaredMethod("getURLStreamHandler", + String.class); + method.setAccessible(true); + return (URLStreamHandler) method.invoke(null, "http"); + } catch (Exception e) { + return null; + } + } + + class CustomHttpHandler extends URLStreamHandler { + @Override + protected URLConnection openConnection(URL u) throws IOException { + return null; + } + } +} \ No newline at end of file