1 /*
   2  * Copyright (c) 2002, 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 4619744
  27  * @summary Test that Process input/out can be concurrently read/written
  28  * @author kladko
  29  */
  30 
  31 import java.io.InputStream;
  32 import java.io.OutputStream;
  33 import java.io.File;
  34 import java.io.IOException;
  35 
  36 public class ConcurrentRead {
  37 
  38     static volatile Exception savedException;
  39     static final String TEE = "/usr/bin/tee";
  40 
  41     public static void main(String[] args) throws Exception {
  42 
  43         if (File.separatorChar == '\\' ||                // Windows
  44                                 !new File(TEE).exists()) // no tee
  45             return;
  46 
  47         Process p = Runtime.getRuntime().exec(TEE);
  48         OutputStream out = p.getOutputStream();
  49         InputStream in = p.getInputStream();
  50         Thread t1 = new WriterThread(out, in);
  51         t1.start();
  52         Thread t2 = new WriterThread(out, in);
  53         t2.start();
  54         t1.join();
  55         t2.join();
  56         if (savedException != null)
  57             throw savedException;
  58     }
  59 
  60     static class WriterThread extends Thread {
  61         OutputStream out;
  62         InputStream in;
  63         WriterThread(OutputStream out, InputStream in) {
  64             this.out = out;
  65             this.in = in;
  66         }
  67         public void run(){
  68             try {
  69                 out.write('a');
  70                 out.flush();
  71                 if (in.read() == -1) // got end-of-stream
  72                     throw new Exception("End of stream in writer thread");
  73             } catch (Exception e) {
  74                 savedException = e;
  75             }
  76         }
  77     }
  78 }