001/* ClassNotFoundException.java -- thrown when class definition cannot be found
002   Copyright (C) 1998, 2002, 2005  Free Software Foundation, Inc.
003
004This file is part of GNU Classpath.
005
006GNU Classpath is free software; you can redistribute it and/or modify
007it under the terms of the GNU General Public License as published by
008the Free Software Foundation; either version 2, or (at your option)
009any later version.
010
011GNU Classpath is distributed in the hope that it will be useful, but
012WITHOUT ANY WARRANTY; without even the implied warranty of
013MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014General Public License for more details.
015
016You should have received a copy of the GNU General Public License
017along with GNU Classpath; see the file COPYING.  If not, write to the
018Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
01902110-1301 USA.
020
021Linking this library statically or dynamically with other modules is
022making a combined work based on this library.  Thus, the terms and
023conditions of the GNU General Public License cover the whole
024combination.
025
026As a special exception, the copyright holders of this library give you
027permission to link this library with independent modules to produce an
028executable, regardless of the license terms of these independent
029modules, and to copy and distribute the resulting executable under
030terms of your choice, provided that you also meet, for each linked
031independent module, the terms and conditions of the license of that
032module.  An independent module is a module which is not derived from
033or based on this library.  If you modify this library, you may extend
034this exception to your version of the library, but you are not
035obligated to do so.  If you do not wish to do so, delete this
036exception statement from your version. */
037
038
039package 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 */
052public 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}