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1   package org.apache.maven.shared.utils.cli;
2   
3   /*
4    * Licensed to the Apache Software Foundation (ASF) under one
5    * or more contributor license agreements.  See the NOTICE file
6    * distributed with this work for additional information
7    * regarding copyright ownership.  The ASF licenses this file
8    * to you under the Apache License, Version 2.0 (the
9    * "License"); you may not use this file except in compliance
10   * with the License.  You may obtain a copy of the License at
11   *
12   *   http://www.apache.org/licenses/LICENSE-2.0
13   *
14   * Unless required by applicable law or agreed to in writing,
15   * software distributed under the License is distributed on an
16   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
17   * KIND, either express or implied.  See the License for the
18   * specific language governing permissions and limitations
19   * under the License.
20   */
21  
22  import java.io.BufferedReader;
23  import java.io.IOException;
24  import java.io.InputStream;
25  import java.io.InputStreamReader;
26  import java.io.PrintWriter;
27  import org.apache.maven.shared.utils.io.IOUtil;
28  
29  /**
30   * Class to pump the error stream during Process's runtime. Copied from the Ant
31   * built-in task.
32   *
33   * @author <a href="mailto:fvancea@maxiq.com">Florin Vancea </a>
34   * @author <a href="mailto:pj@thoughtworks.com">Paul Julius </a>
35   * 
36   */
37  public class StreamPumper
38      extends AbstractStreamHandler
39  {
40      private final BufferedReader in;
41  
42      private final StreamConsumer consumer;
43  
44      private final PrintWriter out;
45  
46      private volatile Exception exception = null;
47  
48      private static final int SIZE = 1024;
49  
50      public StreamPumper( InputStream in, StreamConsumer consumer )
51      {
52          this( in, null, consumer );
53      }
54  
55      private StreamPumper( InputStream in, PrintWriter writer, StreamConsumer consumer )
56      {
57          this.in = new BufferedReader( new InputStreamReader( in ), SIZE );
58          this.out = writer;
59          this.consumer = consumer;
60      }
61  
62      public void run()
63      {
64          try
65          {
66              for ( String line = in.readLine(); line != null; line = in.readLine() )
67              {
68                  try
69                  {
70                      if ( exception == null )
71                      {
72                          consumeLine( line );
73                      }
74                  }
75                  catch ( Exception t )
76                  {
77                      exception = t;
78                  }
79  
80                  if ( out != null )
81                  {
82                      out.println( line );
83  
84                      out.flush();
85                  }
86  
87              }
88          }
89          catch ( IOException e )
90          {
91              exception = e;
92          }
93          finally
94          {
95              IOUtil.close( in );
96  
97              synchronized ( this )
98              {
99                  setDone();
100 
101                 this.notifyAll();
102             }
103         }
104     }
105 
106     public void flush()
107     {
108         if ( out != null )
109         {
110             out.flush();
111         }
112     }
113 
114     public void close()
115     {
116         IOUtil.close( out );
117     }
118 
119     public Exception getException()
120     {
121         return exception;
122     }
123 
124     private void consumeLine( String line )
125     {
126         if ( consumer != null && !isDisabled() )
127         {
128             consumer.consumeLine( line );
129         }
130     }
131 }