1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17 package org.apache.commons.math;
18
19 import java.io.PrintStream;
20 import java.io.PrintWriter;
21 import java.text.MessageFormat;
22 import java.util.Locale;
23 import java.util.MissingResourceException;
24 import java.util.ResourceBundle;
25
26
27 /**
28 * Base class for commons-math checked exceptions.
29 * <p>
30 * Supports nesting, emulating JDK 1.4 behavior if necessary.</p>
31 * <p>
32 * Adapted from <a href="http://commons.apache.org/collections/api-release/org/apache/commons/collections/FunctorException.html"/>.</p>
33 *
34 * @version $Revision: 780674 $ $Date: 2009-06-01 11:10:55 -0400 (Mon, 01 Jun 2009) $
35 */
36 public class MathException extends Exception {
37
38 /** Serializable version identifier. */
39 private static final long serialVersionUID = -9004610152740737812L;
40
41 /**
42 * Pattern used to build the message.
43 */
44 private final String pattern;
45
46 /**
47 * Arguments used to build the message.
48 */
49 private final Object[] arguments;
50
51 /**
52 * Translate a string to a given locale.
53 * @param s string to translate
54 * @param locale locale into which to translate the string
55 * @return translated string or original string
56 * for unsupported locales or unknown strings
57 */
58 private static String translate(String s, Locale locale) {
59 try {
60 ResourceBundle bundle =
61 ResourceBundle.getBundle("org.apache.commons.math.MessagesResources", locale);
62 if (bundle.getLocale().getLanguage().equals(locale.getLanguage())) {
63 // the value of the resource is the translated string
64 return bundle.getString(s);
65 }
66
67 } catch (MissingResourceException mre) {
68 // do nothing here
69 }
70
71 // the locale is not supported or the resource is unknown
72 // don't translate and fall back to using the string as is
73 return s;
74
75 }
76
77 /**
78 * Builds a message string by from a pattern and its arguments.
79 * @param locale Locale in which the message should be translated
80 * @param pattern format specifier
81 * @param arguments format arguments
82 * @return a message string
83 */
84 private static String buildMessage(Locale locale, String pattern, Object ... arguments) {
85 return (pattern == null) ? "" : new MessageFormat(translate(pattern, locale), locale).format(arguments);
86 }
87
88 /**
89 * Constructs a new <code>MathException</code> with no
90 * detail message.
91 */
92 public MathException() {
93 super();
94 this.pattern = null;
95 this.arguments = new Object[0];
96 }
97
98 /**
99 * Constructs a new <code>MathException</code> with specified
100 * formatted detail message.
101 * Message formatting is delegated to {@link java.text.MessageFormat}.
102 * @param pattern format specifier
103 * @param arguments format arguments
104 */
105 public MathException(String pattern, Object ... arguments) {
106 super(buildMessage(Locale.US, pattern, arguments));
107 this.pattern = pattern;
108 this.arguments = (arguments == null) ? new Object[0] : arguments.clone();
109 }
110
111 /**
112 * Constructs a new <code>MathException</code> with specified
113 * nested <code>Throwable</code> root cause.
114 *
115 * @param rootCause the exception or error that caused this exception
116 * to be thrown.
117 */
118 public MathException(Throwable rootCause) {
119 super(rootCause);
120 this.pattern = getMessage();
121 this.arguments = new Object[0];
122 }
123
124 /**
125 * Constructs a new <code>MathException</code> with specified
126 * formatted detail message and nested <code>Throwable</code> root cause.
127 * Message formatting is delegated to {@link java.text.MessageFormat}.
128 * @param rootCause the exception or error that caused this exception
129 * to be thrown.
130 * @param pattern format specifier
131 * @param arguments format arguments
132 * @since 1.2
133 */
134 public MathException(Throwable rootCause, String pattern, Object ... arguments) {
135 super(buildMessage(Locale.US, pattern, arguments), rootCause);
136 this.pattern = pattern;
137 this.arguments = (arguments == null) ? new Object[0] : arguments.clone();
138 }
139
140 /** Gets the pattern used to build the message of this throwable.
141 *
142 * @return the pattern used to build the message of this throwable
143 * @since 1.2
144 */
145 public String getPattern() {
146 return pattern;
147 }
148
149 /** Gets the arguments used to build the message of this throwable.
150 *
151 * @return the arguments used to build the message of this throwable
152 * @since 1.2
153 */
154 public Object[] getArguments() {
155 return arguments.clone();
156 }
157
158 /** Gets the message in a specified locale.
159 *
160 * @param locale Locale in which the message should be translated
161 *
162 * @return localized message
163 * @since 1.2
164 */
165 public String getMessage(Locale locale) {
166 return buildMessage(locale, pattern, arguments);
167 }
168
169 /** {@inheritDoc} */
170 @Override
171 public String getLocalizedMessage() {
172 return getMessage(Locale.getDefault());
173 }
174
175 /**
176 * Prints the stack trace of this exception to the standard error stream.
177 */
178 @Override
179 public void printStackTrace() {
180 printStackTrace(System.err);
181 }
182
183 /**
184 * Prints the stack trace of this exception to the specified stream.
185 *
186 * @param out the <code>PrintStream</code> to use for output
187 */
188 @Override
189 public void printStackTrace(PrintStream out) {
190 synchronized (out) {
191 PrintWriter pw = new PrintWriter(out, false);
192 printStackTrace(pw);
193 // Flush the PrintWriter before it's GC'ed.
194 pw.flush();
195 }
196 }
197
198 }