1 // SAX exception class.
2 // http://www.saxproject.org
3 // No warranty; no copyright -- use this as you will.
4 // $Id: SAXException.java,v 1.7 2002/01/30 21:13:48 dbrownell Exp $
5 
6 package org.xml.sax;
7 
8 /**
9  * Encapsulate a general SAX error or warning.
10  *
11  * <blockquote>
12  * <em>This module, both source code and documentation, is in the
13  * Public Domain, and comes with <strong>NO WARRANTY</strong>.</em>
14  * See <a href='http://www.saxproject.org'>http://www.saxproject.org</a>
15  * for further information.
16  * </blockquote>
17  *
18  * <p>This class can contain basic error or warning information from
19  * either the XML parser or the application: a parser writer or
20  * application writer can subclass it to provide additional
21  * functionality.  SAX handlers may throw this exception or
22  * any exception subclassed from it.</p>
23  *
24  * <p>If the application needs to pass through other types of
25  * exceptions, it must wrap those exceptions in a SAXException
26  * or an exception derived from a SAXException.</p>
27  *
28  * <p>If the parser or application needs to include information about a
29  * specific location in an XML document, it should use the
30  * {@link org.xml.sax.SAXParseException SAXParseException} subclass.</p>
31  *
32  * @since SAX 1.0
33  * @author David Megginson
34  * @version 2.0.1 (sax2r2)
35  * @see org.xml.sax.SAXParseException
36  */
37 public class SAXException extends Exception {
38 
39 
40     /**
41      * Create a new SAXException.
42      */
SAXException()43     public SAXException ()
44     {
45     this.exception = null;
46     }
47 
48 
49     /**
50      * Create a new SAXException.
51      *
52      * @param message The error or warning message.
53      */
SAXException(String message)54     public SAXException (String message) {
55     super(message);
56     this.exception = null;
57     }
58 
59 
60     /**
61      * Create a new SAXException wrapping an existing exception.
62      *
63      * <p>The existing exception will be embedded in the new
64      * one, and its message will become the default message for
65      * the SAXException.</p>
66      *
67      * @param e The exception to be wrapped in a SAXException.
68      */
SAXException(Exception e)69     public SAXException (Exception e)
70     {
71     this.exception = e;
72     }
73 
74 
75     /**
76      * Create a new SAXException from an existing exception.
77      *
78      * <p>The existing exception will be embedded in the new
79      * one, but the new exception will have its own message.</p>
80      *
81      * @param message The detail message.
82      * @param e The exception to be wrapped in a SAXException.
83      */
SAXException(String message, Exception e)84     public SAXException (String message, Exception e)
85     {
86     super(message);
87     this.exception = e;
88     }
89 
90 
91     /**
92      * Return a detail message for this exception.
93      *
94      * <p>If there is an embedded exception, and if the SAXException
95      * has no detail message of its own, this method will return
96      * the detail message from the embedded exception.</p>
97      *
98      * @return The error or warning message.
99      */
getMessage()100     public String getMessage ()
101     {
102     String message = super.getMessage();
103 
104     if (message == null && exception != null) {
105         return exception.getMessage();
106     } else {
107         return message;
108     }
109     }
110 
111 
112     /**
113      * Return the embedded exception, if any.
114      *
115      * @return The embedded exception, or null if there is none.
116      */
getException()117     public Exception getException ()
118     {
119     return exception;
120     }
121 
122 
123     /**
124      * Override toString to pick up any embedded exception.
125      *
126      * @return A string representation of this exception.
127      */
toString()128     public String toString ()
129     {
130     if (exception != null) {
131         return exception.toString();
132     } else {
133         return super.toString();
134     }
135     }
136 
137 
138 
139     //////////////////////////////////////////////////////////////////////
140     // Internal state.
141     //////////////////////////////////////////////////////////////////////
142 
143 
144     /**
145      * @serial The embedded exception if tunnelling, or null.
146      */
147     private Exception exception;
148 
149 }
150 
151 // end of SAXException.java
152