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1   /*
2    * Copyright (c) 1994, 2011, 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 java.lang;
27  
28  /**
29   * Thrown when an application attempts to use {@code null} in a
30   * case where an object is required. These include:
31   * <ul>
32   * <li>Calling the instance method of a {@code null} object.
33   * <li>Accessing or modifying the field of a {@code null} object.
34   * <li>Taking the length of {@code null} as if it were an array.
35   * <li>Accessing or modifying the slots of {@code null} as if it
36   *     were an array.
37   * <li>Throwing {@code null} as if it were a {@code Throwable}
38   *     value.
39   * </ul>
40   * <p>
41   * Applications should throw instances of this class to indicate
42   * other illegal uses of the {@code null} object.
43   *
44   * {@code NullPointerException} objects may be constructed by the
45   * virtual machine as if {@linkplain Throwable#Throwable(String,
46   * Throwable, boolean, boolean) suppression were disabled and/or the
47   * stack trace was not writable}.
48   *
49   * @author  unascribed
50   * @since   JDK1.0
51   */
52  public
53  class NullPointerException extends RuntimeException {
54      private static final long serialVersionUID = 5162710183389028792L;
55  
56      /**
57       * Constructs a {@code NullPointerException} with no detail message.
58       */
59      public NullPointerException() {
60          super();
61      }
62  
63      /**
64       * Constructs a {@code NullPointerException} with the specified
65       * detail message.
66       *
67       * @param   s   the detail message.
68       */
69      public NullPointerException(String s) {
70          super(s);
71      }
72  }