001 /* ClassNotFoundException.java -- thrown when class definition cannot be found
002 Copyright (C) 1998, 2002, 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 java.lang;
040
041 /**
042 * Thrown when a class is requested by reflection, but the class definition
043 * cannot be found. This exception is often chained from another Throwable.
044 *
045 * @author Brian Jones
046 * @author Eric Blake (ebb9@email.byu.edu)
047 * @see Class#forName(String)
048 * @see ClassLoader#findSystemClass(String)
049 * @see ClassLoader#loadClass(String, boolean)
050 * @status updated to 1.4
051 */
052 public class ClassNotFoundException extends Exception
053 {
054 /**
055 * Compatible with JDK 1.0+.
056 */
057 private static final long serialVersionUID = 9176873029745254542L;
058
059 /**
060 * The cause of this exception (duplicates the one stored in Throwable).
061 *
062 * @serial the exception cause
063 * @since 1.2
064 */
065 private final Throwable ex;
066
067 /**
068 * Create an exception without a message. Note that this initializes the
069 * cause to null.
070 */
071 public ClassNotFoundException()
072 {
073 this(null);
074 }
075
076 /**
077 * Create an exception with a message. Note that this initializes the
078 * cause to null.
079 *
080 * @param s the message
081 */
082 public ClassNotFoundException(String s)
083 {
084 super(s);
085 ex = null;
086 }
087
088 /**
089 * Create an exception with a message and chain it to the exception
090 * which occurred while loading the class.
091 *
092 * @param s the message
093 * @param ex the chained exception
094 * @since 1.2
095 */
096 public ClassNotFoundException(String s, Throwable ex)
097 {
098 super(s, ex);
099 this.ex = ex;
100 }
101
102 /**
103 * Returns the exception which occurred while loading the class,
104 * otherwise returns null. This is a legacy method; the preferred choice
105 * now is {@link Throwable#getCause()}.
106 *
107 * @return the cause of this exception
108 * @since 1.2
109 */
110 public Throwable getException()
111 {
112 return ex;
113 }
114
115 /**
116 * Returns the exception which occurred while loading the class,
117 * otherwise returns null.
118 *
119 * @return the cause of this exception
120 * @since 1.4
121 */
122 public Throwable getCause()
123 {
124 return ex;
125 }
126 }