001/*
002 * CDDL HEADER START
003 *
004 * The contents of this file are subject to the terms of the
005 * Common Development and Distribution License, Version 1.0 only
006 * (the "License").  You may not use this file except in compliance
007 * with the License.
008 *
009 * You can obtain a copy of the license at legal-notices/CDDLv1_0.txt
010 * or http://forgerock.org/license/CDDLv1.0.html.
011 * See the License for the specific language governing permissions
012 * and limitations under the License.
013 *
014 * When distributing Covered Code, include this CDDL HEADER in each
015 * file and include the License file at legal-notices/CDDLv1_0.txt.
016 * If applicable, add the following below this CDDL HEADER, with the
017 * fields enclosed by brackets "[]" replaced with your own identifying
018 * information:
019 *      Portions Copyright [yyyy] [name of copyright owner]
020 *
021 * CDDL HEADER END
022 *
023 *
024 *      Copyright 2008 Sun Microsystems, Inc.
025 *      Portions Copyright 2015 ForgeRock AS.
026 */
027
028package org.opends.guitools.controlpanel.util;
029
030import java.io.BufferedReader;
031import java.io.InputStream;
032import java.io.InputStreamReader;
033import java.io.PrintStream;
034
035/**
036 * Class used to write the output and error of a given process in a printstream.
037 *
038 */
039public class ProcessReader
040{
041  private BufferedReader reader;
042  private Thread readerThread;
043  private Throwable lastException;
044  private boolean interrupt;
045  private boolean done;
046
047  /**
048   * The constructor.
049   * @param process process whose output/error we want to write to the print
050   * stream.
051   * @param printStream the print stream.
052   * @param isError whether we must write the error (or the output) must be
053   * written to the stream.
054   */
055  public ProcessReader(Process process, final PrintStream printStream,
056      boolean isError)
057  {
058    InputStream is;
059    if (isError)
060    {
061      is = process.getErrorStream();
062    }
063    else
064    {
065      is = process.getInputStream();
066    }
067    reader = new BufferedReader(new InputStreamReader(is));
068
069    readerThread = new Thread(new Runnable()
070    {
071      /** {@inheritDoc} */
072      public void run()
073      {
074        String line;
075        try
076        {
077          while (!interrupt && (null != (line = reader.readLine())))
078          {
079            printStream.println(line);
080          }
081        }
082        catch (Throwable t)
083        {
084          lastException = t;
085        }
086        done = true;
087      }
088    });
089  }
090
091  /**
092   * Starts reading the output (or error) of the process.
093   *
094   */
095  public void startReading()
096  {
097    readerThread.start();
098  }
099
100  /**
101   * Interrupts the reading of the output (or error) of the process.  The method
102   * does not return until the reading is over.
103   *
104   */
105  public void interrupt()
106  {
107    interrupt = true;
108    while (!done)
109    {
110      try
111      {
112        readerThread.interrupt();
113      }
114      catch (Throwable t)
115      {
116      }
117    }
118  }
119
120  /**
121   * Returns the last exception that occurred reading the output (or the error)
122   * of the process.
123   * @return the last exception that occurred reading the output (or the error)
124   * of the process.
125   */
126  public Throwable getLastException()
127  {
128    return lastException;
129  }
130}