1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one or more 3 * contributor license agreements. See the NOTICE file distributed with 4 * this work for additional information regarding copyright ownership. 5 * The ASF licenses this file to You under the Apache License, Version 2.0 6 * (the "License"); you may not use this file except in compliance with 7 * the License. You may obtain a copy of the License at 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the License for the specific language governing permissions and 15 * limitations under the License. 16 */ 17 18 package java.lang; 19 20 /** 21 * Thrown when a program tries to access a field or method of an object or an 22 * element of an array when there is no instance or array to use, that is if the 23 * object or array points to {@code null}. It also occurs in some other, less 24 * obvious circumstances, like a {@code throw e} statement where the {@link 25 * Throwable} reference is {@code null}. 26 */ 27 public class NullPointerException extends RuntimeException { 28 29 private static final long serialVersionUID = 5162710183389028792L; 30 31 /** 32 * Constructs a new {@code NullPointerException} that includes the current 33 * stack trace. 34 */ NullPointerException()35 public NullPointerException() { 36 } 37 38 /** 39 * Constructs a new {@code NullPointerException} with the current stack 40 * trace and the specified detail message. 41 * 42 * @param detailMessage 43 * the detail message for this exception. 44 */ NullPointerException(String detailMessage)45 public NullPointerException(String detailMessage) { 46 super(detailMessage); 47 } 48 49 } 50