org.springframework.web.servlet.FlashMapManager Maven / Gradle / Ivy
/*
* Copyright 2002-2014 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* https://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.web.servlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.springframework.lang.Nullable;
/**
* A strategy interface for retrieving and saving FlashMap instances.
* See {@link FlashMap} for a general overview of flash attributes.
*
* @author Rossen Stoyanchev
* @since 3.1
* @see FlashMap
*/
public interface FlashMapManager {
/**
* Find a FlashMap saved by a previous request that matches to the current
* request, remove it from underlying storage, and also remove other
* expired FlashMap instances.
* This method is invoked in the beginning of every request in contrast
* to {@link #saveOutputFlashMap}, which is invoked only when there are
* flash attributes to be saved - i.e. before a redirect.
* @param request the current request
* @param response the current response
* @return a FlashMap matching the current request or {@code null}
*/
@Nullable
FlashMap retrieveAndUpdate(HttpServletRequest request, HttpServletResponse response);
/**
* Save the given FlashMap, in some underlying storage and set the start
* of its expiration period.
*
NOTE: Invoke this method prior to a redirect in order
* to allow saving the FlashMap in the HTTP session or in a response
* cookie before the response is committed.
* @param flashMap the FlashMap to save
* @param request the current request
* @param response the current response
*/
void saveOutputFlashMap(FlashMap flashMap, HttpServletRequest request, HttpServletResponse response);
}