Java example source code file (DeleteOnExitNPE.java)

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Java - Java tags/keywords

bufferedreader, deleteonexitnpe, exception, failed, file, illegalstateexception, interruptedexception, ioexception, process, runnable, runtimeexception, string, thread

The DeleteOnExitNPE.java Java example source code

/*
 * Copyright (c) 2007, 2010, 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  6526376
   @summary DeleteOnExitHook.add() produces NullPointerException
 */

import java.io.*;

/* NullPointerException in exec'ed process if fails.
 * This testcase is timing sensitive. It may sometimes pass even with this bug
 * present, but will never fail without it.
 */

public class DeleteOnExitNPE implements Runnable
{
    public static void main(String[] args) throws Exception {
        if (args.length == 0) {
            runTest();
        } else {
            doTest();
        }
    }

    public static void runTest() throws Exception {
        String cmd = System.getProperty("java.home") + File.separator +
                     "bin" + File.separator + "java" +
                     " -classpath " + System.getProperty("test.classes");
        Process process = Runtime.getRuntime().exec(cmd +  " DeleteOnExitNPE -test");
        BufferedReader isReader = new BufferedReader(new InputStreamReader(process.getInputStream()));
        BufferedReader esReader = new BufferedReader(new InputStreamReader(process.getErrorStream()));

        process.waitFor();

        boolean failed = false;
        String str;
        while ((str = isReader.readLine()) != null) {
            failed = true;
            System.out.println(str);
        }
        while ((str = esReader.readLine()) != null) {
            failed = true;
            System.err.println(str);
        }

        if (failed)
            throw new RuntimeException("Failed: No output should have been received from the process");
    }

    public static void doTest() {
        try {
            File file = File.createTempFile("DeleteOnExitNPE", null);
            file.deleteOnExit();

            Thread thread = new Thread(new DeleteOnExitNPE());
            thread.start();

            try {
                Thread.sleep(2000);
            } catch (InterruptedException ie) {
                ie.printStackTrace();
            }

            System.exit(0);
        } catch (IOException ioe) {
            ioe.printStackTrace();
        }
    }

    public void run() {
        File file = new File("xxyyzz");

        try {
            for (;;) {
                file.deleteOnExit();
            }
        } catch (IllegalStateException ise) {
            // ignore. This is ok.
            // Trying to add a file to the list of files marked as deleteOnExit when
            // shutdown is in progress and the DeleteOnExitHook is running.
        }
    }
}