001 /* NullPointerException.java -- thrown when using null instead of an object 002 Copyright (C) 1998, 1999, 2001, 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 attempting to use <code>null</code> where an object 043 * is required. The Virtual Machine automatically throws this exception 044 * for the following:<br><ul> 045 * <li>Calling an instance method on a null object</li> 046 * <li>Accessing or modifying a field of a null object</li> 047 * <li>Taking the array length of a null array</li> 048 * <li>Accessing or modifying the slots of a null array</li> 049 * <li>Throwing a null Throwable</li> 050 * <li>Synchronizing on a null object</li> 051 * </ul> 052 * <p>Applications should also throw NullPointerExceptions whenever 053 * <code>null</code> is an inappropriate parameter to a method. 054 * 055 * @author Brian Jones 056 * @author Warren Levy (warrenl@cygnus.com) 057 * @status updated to 1.4 058 */ 059 public class NullPointerException extends RuntimeException 060 { 061 /** 062 * Compatible with JDK 1.0+. 063 */ 064 private static final long serialVersionUID = 5162710183389028792L; 065 066 /** 067 * Create an exception without a message. 068 */ 069 public NullPointerException() 070 { 071 } 072 073 /** 074 * Create an exception with a message. 075 * 076 * @param s the message 077 */ 078 public NullPointerException(String s) 079 { 080 super(s); 081 } 082 }