001    /* SaslException.java
002       Copyright (C) 2003, 2005, Free Software Foundation, Inc.
003    
004    This file is part of GNU Classpath.
005    
006    GNU Classpath is free software; you can redistribute it and/or modify
007    it under the terms of the GNU General Public License as published by
008    the Free Software Foundation; either version 2, or (at your option)
009    any later version.
010    
011    GNU Classpath is distributed in the hope that it will be useful, but
012    WITHOUT ANY WARRANTY; without even the implied warranty of
013    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014    General Public License for more details.
015    
016    You should have received a copy of the GNU General Public License
017    along with GNU Classpath; see the file COPYING.  If not, write to the
018    Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
019    02110-1301 USA.
020    
021    Linking this library statically or dynamically with other modules is
022    making a combined work based on this library.  Thus, the terms and
023    conditions of the GNU General Public License cover the whole
024    combination.
025    
026    As a special exception, the copyright holders of this library give you
027    permission to link this library with independent modules to produce an
028    executable, regardless of the license terms of these independent
029    modules, and to copy and distribute the resulting executable under
030    terms of your choice, provided that you also meet, for each linked
031    independent module, the terms and conditions of the license of that
032    module.  An independent module is a module which is not derived from
033    or based on this library.  If you modify this library, you may extend
034    this exception to your version of the library, but you are not
035    obligated to do so.  If you do not wish to do so, delete this
036    exception statement from your version. */
037    
038    
039    package javax.security.sasl;
040    
041    import gnu.java.lang.CPStringBuilder;
042    
043    import java.io.IOException;
044    import java.io.PrintStream;
045    import java.io.PrintWriter;
046    import java.io.Serializable;
047    
048    /**
049     * This class represents an error that has occurred when using SASL.
050     *
051     * @since 1.5
052     */
053    public class SaslException extends IOException implements Serializable
054    {
055    
056      // Constants and variables
057      // -------------------------------------------------------------------------
058    
059      private static final long serialVersionUID = 4579784287983423626L;
060    
061      /**
062       * @serial The possibly null root cause exception.
063       */
064      private Throwable _exception = null;
065    
066      // Constructor(s)
067      // -------------------------------------------------------------------------
068    
069      /**
070       * Constructs a new instance of <code>SaslException</code>. The root
071       * exception and the detailed message are null.
072       */
073      public SaslException()
074      {
075        super();
076      }
077    
078      /**
079       * Constructs a new instance of <code>SaslException</code> with a detailed
080       * message. The <code>root</code> exception is <code>null</code>.
081       *
082       * @param detail a possibly null string containing details of the exception.
083       * @see Throwable#getMessage()
084       */
085      public SaslException(String detail)
086      {
087        super(detail);
088      }
089    
090      /**
091       * Constructs a new instance of <code>SaslException</code> with a detailed
092       * message and a root exception. For example, a <code>SaslException</code>
093       * might result from a problem with the callback handler, which might throw a
094       * {@link javax.security.auth.callback.UnsupportedCallbackException} if it
095       * does not support the requested callback, or throw an {@link IOException}
096       * if it had problems obtaining data for the callback. The
097       * <code>SaslException</code>'s root exception would be then be the exception
098       * thrown by the callback handler.
099       *
100       * @param detail a possibly <code>null</code> string containing details of
101       * the exception.
102       * @param ex a possibly <code>null</code> root exception that caused this
103       * exception.
104       * @see Throwable#getMessage()
105       * @see #getCause()
106       */
107      public SaslException(String detail, Throwable ex)
108      {
109        super(detail);
110        _exception = ex;
111      }
112    
113      // Class methods
114      // -------------------------------------------------------------------------
115    
116      // Instance methods
117      // -------------------------------------------------------------------------
118    
119      /**
120       * Returns the cause of this throwable or <code>null</code> if the cause is
121       * nonexistent or unknown. The cause is the throwable that caused this
122       * exception to be thrown.
123       *
124       * @return the possibly <code>null</code> exception that caused this exception.
125       */
126      public Throwable getCause()
127      {
128        return _exception;
129      }
130    
131      /**
132       * Prints this exception's stack trace to <code>System.err</code>. If this
133       * exception has a root exception; the stack trace of the root exception is
134       * also printed to <code>System.err</code>.
135       */
136      public void printStackTrace()
137      {
138        super.printStackTrace();
139        if (_exception != null)
140          _exception.printStackTrace();
141      }
142    
143      /**
144       * Prints this exception's stack trace to a print stream. If this exception
145       * has a root exception; the stack trace of the root exception is also
146       * printed to the print stream.
147       *
148       * @param ps the non-null print stream to which to print.
149       */
150      public void printStackTrace(PrintStream ps)
151      {
152        super.printStackTrace(ps);
153        if (_exception != null)
154          _exception.printStackTrace(ps);
155      }
156    
157      /**
158       * Prints this exception's stack trace to a print writer. If this exception
159       * has a root exception; the stack trace of the root exception is also
160       * printed to the print writer.
161       *
162       * @param pw the non-null print writer to use for output.
163       */
164      public void printStackTrace(PrintWriter pw)
165      {
166        super.printStackTrace(pw);
167        if (_exception != null)
168          _exception.printStackTrace(pw);
169      }
170    
171      /**
172       * Returns the string representation of this exception. The string
173       * representation contains this exception's class name, its detailed
174       * messsage, and if it has a root exception, the string representation of the
175       * root exception. This string representation is meant for debugging and not
176       * meant to be interpreted programmatically.
177       *
178       * @return the non-null string representation of this exception.
179       * @see Throwable#getMessage()
180       */
181      public String toString()
182      {
183        CPStringBuilder sb = new CPStringBuilder(this.getClass().getName())
184          .append(": ").append(super.toString());
185        if (_exception != null)
186          sb.append("; caused by: ").append(_exception.toString());
187        return sb.toString();
188      }
189    }