1 /* 2 * Copyright (c) 2003, 2017, 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 import java.io.InvalidClassException; 34 35 /** 36 * {@code XPathException} represents a generic XPath exception. 37 * 38 * @author <a href="Norman.Walsh@Sun.com">Norman Walsh</a> 39 * @author <a href="mailto:Jeff.Suttor@Sun.COM">Jeff Suttor</a> 40 * @since 1.5 41 */ 42 public class XPathException extends Exception { 43 44 private static final ObjectStreamField[] serialPersistentFields = { 45 new ObjectStreamField( "cause", Throwable.class ) 46 }; 47 48 /** 49 * Stream Unique Identifier. 50 */ 51 private static final long serialVersionUID = -1837080260374986980L; 52 53 /** 54 * Constructs a new {@code XPathException} 55 * with the specified detail {@code message}. 56 * 57 * <p>The {@code cause} is not initialized. 58 * 59 * <p>If {@code message} is {@code null}, 60 * then a {@code NullPointerException} is thrown. 61 * 62 * @param message The detail message. 63 * 64 * @throws NullPointerException When {@code message} is 65 * {@code null}. 66 */ 67 public XPathException(String message) { 68 super(message); 69 if ( message == null ) { 70 throw new NullPointerException ( "message can't be null"); 71 } 72 } 73 74 /** 75 * Constructs a new {@code XPathException} 76 * with the specified {@code cause}. 77 * 78 * <p>If {@code cause} is {@code null}, 79 * then a {@code NullPointerException} is thrown. 80 * 81 * @param cause The cause. 82 * 83 * @throws NullPointerException if {@code cause} is {@code null}. 84 */ 85 public XPathException(Throwable cause) { 86 super(cause); 87 if ( cause == null ) { 88 throw new NullPointerException ( "cause can't be null"); 89 } 90 } 91 92 /** 93 * Get the cause of this XPathException. 94 * 95 * @return Cause of this XPathException. 96 */ 97 public Throwable getCause() { 98 return super.getCause(); 99 } 100 101 /** 102 * Writes "cause" field to the stream. 103 * The cause is got from the parent class. 104 * 105 * @param out stream used for serialization. 106 * @throws IOException thrown by {@code ObjectOutputStream} 107 * 108 */ 109 private void writeObject(ObjectOutputStream out) 110 throws IOException 111 { 112 ObjectOutputStream.PutField fields = out.putFields(); 113 fields.put("cause", super.getCause()); 114 out.writeFields(); 115 } 116 117 /** 118 * Reads the "cause" field from the stream. 119 * And initializes the "cause" if it wasn't 120 * done before. 121 * 122 * @param in stream used for deserialization 123 * @throws IOException thrown by {@code ObjectInputStream} 124 * @throws ClassNotFoundException thrown by {@code ObjectInputStream} 125 */ 126 private void readObject(ObjectInputStream in) 127 throws IOException, ClassNotFoundException 128 { 129 ObjectInputStream.GetField fields = in.readFields(); 130 Throwable scause = (Throwable) fields.get("cause", null); 131 132 if (super.getCause() == null && scause != null) { 133 try { 134 super.initCause(scause); 135 } catch(IllegalStateException e) { 136 throw new InvalidClassException("Inconsistent state: two causes"); 137 } 138 } 139 } 140 141 /** 142 * Print stack trace to specified {@code PrintStream}. 143 * 144 * @param s Print stack trace to this {@code PrintStream}. 145 */ 146 public void printStackTrace(java.io.PrintStream s) { 147 if (getCause() != null) { 148 getCause().printStackTrace(s); 149 s.println("--------------- linked to ------------------"); 150 } 151 152 super.printStackTrace(s); 153 } 154 155 /** 156 * Print stack trace to {@code System.err}. 157 */ 158 public void printStackTrace() { 159 printStackTrace(System.err); 160 } 161 162 /** 163 * Print stack trace to specified {@code PrintWriter}. 164 * 165 * @param s Print stack trace to this {@code PrintWriter}. 166 */ 167 public void printStackTrace(PrintWriter s) { 168 169 if (getCause() != null) { 170 getCause().printStackTrace(s); 171 s.println("--------------- linked to ------------------"); 172 } 173 174 super.printStackTrace(s); 175 } 176 }