/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package peasy.org.apache.commons.math;
import java.io.PrintStream;
import java.io.PrintWriter;
import java.text.MessageFormat;
import java.util.Locale;
import java.util.MissingResourceException;
import java.util.ResourceBundle;
/**
* Base class for commons-math checked exceptions.
* <p>
* Supports nesting, emulating JDK 1.4 behavior if necessary.
* </p>
* <p>
*
* @version $Revision: 620312 $ $Date: 2008-02-10 12:28:59 -0700 (Sun, 10 Feb
* 2008) $
*/
public class MathException extends Exception {
/** Serializable version identifier */
private static final long serialVersionUID = -8602234299177097102L;
/**
* Does JDK support nested exceptions?
*/
private static final boolean JDK_SUPPORTS_NESTED;
static {
boolean flag = false;
try {
Throwable.class.getDeclaredMethod("getCause", new Class[0]);
flag = true;
} catch (final NoSuchMethodException ex) {
flag = false;
}
JDK_SUPPORTS_NESTED = flag;
}
/** Cache for resources bundle. */
private static ResourceBundle cachedResources = null;
/**
* Pattern used to build the message.
*/
private final String pattern;
/**
* Arguments used to build the message.
*/
private final Object[] arguments;
/**
* Root cause of the exception
*/
private final Throwable rootCause;
/**
* Translate a string to a given locale.
*
* @param s
* string to translate
* @param locale
* locale into which to translate the string
* @return translated string or original string for unsupported locales or
* unknown strings
*/
private static String translate(final String s, final Locale locale) {
try {
if ((cachedResources == null)
|| (!cachedResources.getLocale().equals(locale))) {
// caching the resource bundle
cachedResources = ResourceBundle.getBundle(
"peasy.org.apache.commons.math.MessagesResources", locale);
}
if (cachedResources.getLocale().getLanguage().equals(locale.getLanguage())) {
// the value of the resource is the translated string
return cachedResources.getString(s);
}
} catch (final MissingResourceException mre) {
// do nothing here
}
// the locale is not supported or the resource is unknown
// don't translate and fall back to using the string as is
return s;
}
/**
* Builds a message string by from a pattern and its arguments.
*
* @param pattern
* format specifier
* @param arguments
* format arguments
* @param locale
* Locale in which the message should be translated
* @return a message string
*/
private static String buildMessage(final String pattern, final Object[] arguments,
final Locale locale) {
// do it the hard way, for Java 1.3. compatibility
final MessageFormat mf = new MessageFormat(translate(pattern, locale));
mf.setLocale(locale);
return mf.format(arguments);
}
/**
* Constructs a new <code>MathException</code> with no detail message.
*/
public MathException() {
super();
this.pattern = null;
this.arguments = new Object[0];
this.rootCause = null;
}
/**
* Constructs a new <code>MathException</code> with specified detail
* message.
*
* @param msg
* the error message.
* @deprecated as of 1.2, replaced by
* {@link #MathException(String, Object[])}
*/
@Deprecated
public MathException(final String msg) {
super(msg);
this.pattern = msg;
this.arguments = new Object[0];
this.rootCause = null;
}
/**
* Constructs a new <code>MathException</code> with specified formatted
* detail message. Message formatting is delegated to
* {@link java.text.MessageFormat}.
*
* @param pattern
* format specifier
* @param arguments
* format arguments
*/
public MathException(final String pattern, final Object[] arguments) {
super(buildMessage(pattern, arguments, Locale.US));
this.pattern = pattern;
this.arguments = arguments.clone();
this.rootCause = null;
}
/**
* Constructs a new <code>MathException</code> with specified nested
* <code>Throwable</code> root cause.
*
* @param rootCause
* the exception or error that caused this exception to be
* thrown.
*/
public MathException(final Throwable rootCause) {
super((rootCause == null ? null : rootCause.getMessage()));
this.pattern = getMessage();
this.arguments = new Object[0];
this.rootCause = rootCause;
}
/**
* Constructs a new <code>MathException</code> with specified detail message
* and nested <code>Throwable</code> root cause.
*
* @param msg
* the error message.
* @param rootCause
* the exception or error that caused this exception to be
* thrown.
* @deprecated as of 1.2, replaced by
* {@link #MathException(String, Object[], Throwable)}
*/
@Deprecated
public MathException(final String msg, final Throwable rootCause) {
super(msg);
this.pattern = msg;
this.arguments = new Object[0];
this.rootCause = rootCause;
}
/**
* Constructs a new <code>MathException</code> with specified formatted
* detail message and nested <code>Throwable</code> root cause. Message
* formatting is delegated to {@link java.text.MessageFormat}.
*
* @param pattern
* format specifier
* @param arguments
* format arguments
* @param rootCause
* the exception or error that caused this exception to be
* thrown.
* @since 1.2
*/
public MathException(final String pattern, final Object[] arguments,
final Throwable rootCause) {
super(buildMessage(pattern, arguments, Locale.US));
this.pattern = pattern;
this.arguments = arguments.clone();
this.rootCause = rootCause;
}
/**
* Gets the pattern used to build the message of this throwable.
*
* @return the pattern used to build the message of this throwable
* @since 1.2
*/
public String getPattern() {
return pattern;
}
/**
* Gets the arguments used to build the message of this throwable.
*
* @return the arguments used to build the message of this throwable
* @since 1.2
*/
public Object[] getArguments() {
return arguments.clone();
}
/**
* Gets the message in a specified locale.
*
* @param locale
* Locale in which the message should be translated
*
* @return localized message
* @since 1.2
*/
public String getMessage(final Locale locale) {
return (pattern == null) ? null : buildMessage(pattern, arguments, locale);
}
/**
* Gets the cause of this throwable.
*
* @return the cause of this throwable, or <code>null</code>
*/
@Override
public Throwable getCause() {
return rootCause;
}
/**
* Prints the stack trace of this exception to the standard error stream.
*/
@Override
public void printStackTrace() {
printStackTrace(System.err);
}
/**
* Prints the stack trace of this exception to the specified stream.
*
* @param out
* the <code>PrintStream</code> to use for output
*/
@Override
public void printStackTrace(final PrintStream out) {
synchronized (out) {
final PrintWriter pw = new PrintWriter(out, false);
printStackTrace(pw);
// Flush the PrintWriter before it's GC'ed.
pw.flush();
}
}
/**
* Prints the stack trace of this exception to the specified writer.
*
* @param out
* the <code>PrintWriter</code> to use for output
*/
@Override
public void printStackTrace(final PrintWriter out) {
synchronized (out) {
super.printStackTrace(out);
if (rootCause != null && JDK_SUPPORTS_NESTED == false) {
out.print("Caused by: ");
rootCause.printStackTrace(out);
}
}
}
}