1 package org.apache.maven.shared.invoker;
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.PrintStream;
23
24 /**
25 * Offers an output handler that writes to a print stream like {@link java.lang.System#out}.
26 *
27 * @since 2.0.9
28 */
29 public class PrintStreamHandler
30 implements InvocationOutputHandler
31 {
32
33 /**
34 * The print stream to write to, never <code>null</code>.
35 */
36 private PrintStream out;
37
38 /**
39 * A flag whether the print stream should be flushed after each line.
40 */
41 private boolean alwaysFlush;
42
43 /**
44 * Creates a new output handler that writes to {@link java.lang.System#out}.
45 */
46 public PrintStreamHandler()
47 {
48 this( System.out, false );
49 }
50
51 /**
52 * Creates a new output handler that writes to the specified print stream.
53 *
54 * @param out The print stream to write to, must not be <code>null</code>.
55 * @param alwaysFlush A flag whether the print stream should be flushed after each line.
56 */
57 public PrintStreamHandler( PrintStream out, boolean alwaysFlush )
58 {
59 if ( out == null )
60 {
61 throw new NullPointerException( "missing output stream" );
62 }
63 this.out = out;
64 this.alwaysFlush = alwaysFlush;
65 }
66
67 /** {@inheritDoc} */
68 public void consumeLine( String line )
69 {
70 if ( line == null )
71 {
72 out.println();
73 }
74 else
75 {
76 out.println( line );
77 }
78
79 if ( alwaysFlush )
80 {
81 out.flush();
82 }
83 }
84
85 }