1 //******************************************************************************
2 //
3 // File: PrintStreamLogger.java
4 // Package: edu.rit.util
5 // Unit: Class edu.rit.util.PrintStreamLogger
6 //
7 // This Java source file is copyright (C) 2008 by Alan Kaminsky. All rights
8 // reserved. For further information, contact the author, Alan Kaminsky, at
9 // ark@cs.rit.edu.
10 //
11 // This Java source file is part of the Parallel Java Library ("PJ"). PJ is free
12 // software; you can redistribute it and/or modify it under the terms of the GNU
13 // General Public License as published by the Free Software Foundation; either
14 // version 3 of the License, or (at your option) any later version.
15 //
16 // PJ is distributed in the hope that it will be useful, but WITHOUT ANY
17 // WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
18 // A PARTICULAR PURPOSE. See the GNU General Public License for more details.
19 //
20 // Linking this library statically or dynamically with other modules is making a
21 // combined work based on this library. Thus, the terms and conditions of the GNU
22 // General Public License cover the whole combination.
23 //
24 // As a special exception, the copyright holders of this library give you
25 // permission to link this library with independent modules to produce an
26 // executable, regardless of the license terms of these independent modules, and
27 // to copy and distribute the resulting executable under terms of your choice,
28 // provided that you also meet, for each linked independent module, the terms
29 // and conditions of the license of that module. An independent module is a module
30 // which is not derived from or based on this library. If you modify this library,
31 // you may extend this exception to your version of the library, but you are not
32 // obligated to do so. If you do not wish to do so, delete this exception
33 // statement from your version.
34 //
35 // A copy of the GNU General Public License is provided in the file gpl.txt. You
36 // may also obtain a copy of the GNU General Public License on the World Wide
37 // Web at http://www.gnu.org/licenses/gpl.html.
38 //
39 //******************************************************************************
40 package edu.rit.util;
41
42 import java.io.PrintStream;
43 import java.util.Date;
44
45 /**
46 * Class PrintStreamLogger provides an object that logs messages to a print
47 * stream.
48 *
49 * @author Alan Kaminsky
50 * @version 16-Apr-2008
51 */
52 public class PrintStreamLogger
53 implements Logger {
54
55 // Hidden operations.
56 private PrintStream out;
57
58 // Exported constructors.
59 /**
60 * Construct a new print stream logger that logs to <code>System.err</code>.
61 */
62 public PrintStreamLogger() {
63 this.out = System.err;
64 }
65
66 /**
67 * Construct a new print stream logger that logs to the given print stream.
68 *
69 * @param out Print stream.
70 * @exception NullPointerException (unchecked exception) Thrown if
71 * <code>out</code> is null.
72 */
73 public PrintStreamLogger(PrintStream out) {
74 if (out == null) {
75 throw new NullPointerException("PrintStreamLogger(): Print stream is null");
76 }
77 this.out = out;
78 }
79
80 // Exported operations.
81 /**
82 * Log the given message.
83 *
84 * @param msg Message.
85 */
86 public void log(String msg) {
87 log(System.currentTimeMillis(), msg, null);
88 }
89
90 /**
91 * {@inheritDoc}
92 *
93 * Log the given exception.
94 */
95 public void log(Throwable exc) {
96 log(System.currentTimeMillis(), null, exc);
97 }
98
99 /**
100 * {@inheritDoc}
101 *
102 * Log the given message and exception.
103 */
104 public void log(String msg,
105 Throwable exc) {
106 log(System.currentTimeMillis(), msg, exc);
107 }
108
109 /**
110 * Log the given date and message.
111 *
112 * @param date Date and time in milliseconds since midnight 01-Jan-1970 UTC.
113 * @param msg Message.
114 */
115 public void log(long date,
116 String msg) {
117 log(date, msg, null);
118 }
119
120 /**
121 * {@inheritDoc}
122 *
123 * Log the given date and exception.
124 */
125 public void log(long date,
126 Throwable exc) {
127 log(date, null, exc);
128 }
129
130 /**
131 * {@inheritDoc}
132 *
133 * Log the given date, message, and exception.
134 */
135 public void log(long date,
136 String msg,
137 Throwable exc) {
138 synchronized (out) {
139 out.print(new Date(date));
140 if (msg != null) {
141 out.print(' ');
142 out.print(msg);
143 }
144 out.println();
145 if (exc != null) {
146 exc.printStackTrace(out);
147 }
148 }
149 }
150
151 }