1 /*
2 * Copyright (c) 2003, 2005, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package javax.xml.xpath;
27
28 import java.io.PrintWriter;
29 import java.io.IOException;
30 import java.io.ObjectInputStream;
31 import java.io.ObjectOutputStream;
32 import java.io.ObjectStreamField;
33
34 /**
35 * <code>XPathException</code> represents a generic XPath exception.</p>
36 *
37 * @author <a href="Norman.Walsh@Sun.com">Norman Walsh</a>
38 * @author <a href="mailto:Jeff.Suttor@Sun.COM">Jeff Suttor</a>
39 * @since 1.5
40 */
41 public class XPathException extends Exception {
42
43 private static final ObjectStreamField[] serialPersistentFields = {
44 new ObjectStreamField( "cause", Throwable.class )
45 };
46
47 /**
48 * <p>Stream Unique Identifier.</p>
49 */
50 private static final long serialVersionUID = -1837080260374986980L;
51
52 /**
53 * <p>Constructs a new <code>XPathException</code>
54 * with the specified detail <code>message</code>.</p>
55 *
56 * <p>The <code>cause</code> is not initialized.</p>
57 *
58 * <p>If <code>message</code> is <code>null</code>,
59 * then a <code>NullPointerException</code> is thrown.</p>
60 *
61 * @param message The detail message.
62 *
63 * @throws NullPointerException When <code>message</code> is
64 * <code>null</code>.
65 */
66 public XPathException(String message) {
67 super(message);
68 if ( message == null ) {
69 throw new NullPointerException ( "message can't be null");
70 }
71 }
72
73 /**
74 * <p>Constructs a new <code>XPathException</code>
75 * with the specified <code>cause</code>.</p>
76 *
77 * <p>If <code>cause</code> is <code>null</code>,
78 * then a <code>NullPointerException</code> is thrown.</p>
79 *
80 * @param cause The cause.
81 *
82 * @throws NullPointerException if <code>cause</code> is <code>null</code>.
83 */
84 public XPathException(Throwable cause) {
85 super(cause);
86 if ( cause == null ) {
87 throw new NullPointerException ( "cause can't be null");
88 }
89 }
90
91 /**
92 * <p>Get the cause of this XPathException.</p>
93 *
94 * @return Cause of this XPathException.
95 */
96 public Throwable getCause() {
97 return super.getCause();
98 }
99
100 /**
101 * Writes "cause" field to the stream.
102 * The cause is got from the parent class.
103 *
104 * @param out stream used for serialization.
105 * @throws IOException thrown by <code>ObjectOutputStream</code>
106 *
107 */
108 private void writeObject(ObjectOutputStream out)
109 throws IOException
110 {
111 ObjectOutputStream.PutField fields = out.putFields();
112 fields.put("cause", (Throwable) super.getCause());
113 out.writeFields();
114 }
115
116 /**
117 * Reads the "cause" field from the stream.
118 * And initializes the "cause" if it wasn't
119 * done before.
120 *
121 * @param in stream used for deserialization
122 * @throws IOException thrown by <code>ObjectInputStream</code>
123 * @throws ClassNotFoundException thrown by <code>ObjectInputStream</code>
124 */
125 private void readObject(ObjectInputStream in)
126 throws IOException, ClassNotFoundException
127 {
128 ObjectInputStream.GetField fields = in.readFields();
129 Throwable scause = (Throwable) fields.get("cause", null);
130 if (super.getCause() == null && scause != null)
131 super.initCause(scause);
132 }
133
134 /**
135 * <p>Print stack trace to specified <code>PrintStream</code>.</p>
136 *
137 * @param s Print stack trace to this <code>PrintStream</code>.
138 */
139 public void printStackTrace(java.io.PrintStream s) {
140 if (getCause() != null) {
141 getCause().printStackTrace(s);
142 s.println("--------------- linked to ------------------");
143 }
144
145 super.printStackTrace(s);
146 }
147
148 /**
149 * <p>Print stack trace to <code>System.err</code>.</p>
150 */
151 public void printStackTrace() {
152 printStackTrace(System.err);
153 }
154
155 /**
156 * <p>Print stack trace to specified <code>PrintWriter</code>.</p>
157 *
158 * @param s Print stack trace to this <code>PrintWriter</code>.
159 */
160 public void printStackTrace(PrintWriter s) {
161
162 if (getCause() != null) {
163 getCause().printStackTrace(s);
164 s.println("--------------- linked to ------------------");
165 }
166
167 super.printStackTrace(s);
168 }
169 }