001/* 002 * Copyright 2002-2018 the original author or authors. 003 * 004 * Licensed under the Apache License, Version 2.0 (the "License"); 005 * you may not use this file except in compliance with the License. 006 * You may obtain a copy of the License at 007 * 008 * https://www.apache.org/licenses/LICENSE-2.0 009 * 010 * Unless required by applicable law or agreed to in writing, software 011 * distributed under the License is distributed on an "AS IS" BASIS, 012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 013 * See the License for the specific language governing permissions and 014 * limitations under the License. 015 */ 016 017package org.springframework.web; 018 019import javax.servlet.ServletException; 020 021import org.springframework.lang.Nullable; 022 023/** 024 * Exception thrown when an HTTP request handler requires a pre-existing session. 025 * 026 * @author Juergen Hoeller 027 * @since 2.0 028 */ 029@SuppressWarnings("serial") 030public class HttpSessionRequiredException extends ServletException { 031 032 @Nullable 033 private final String expectedAttribute; 034 035 036 /** 037 * Create a new HttpSessionRequiredException. 038 * @param msg the detail message 039 */ 040 public HttpSessionRequiredException(String msg) { 041 super(msg); 042 this.expectedAttribute = null; 043 } 044 045 /** 046 * Create a new HttpSessionRequiredException. 047 * @param msg the detail message 048 * @param expectedAttribute the name of the expected session attribute 049 * @since 4.3 050 */ 051 public HttpSessionRequiredException(String msg, String expectedAttribute) { 052 super(msg); 053 this.expectedAttribute = expectedAttribute; 054 } 055 056 057 /** 058 * Return the name of the expected session attribute, if any. 059 * @since 4.3 060 */ 061 @Nullable 062 public String getExpectedAttribute() { 063 return this.expectedAttribute; 064 } 065 066}