Spring Framework example source code file (AbstractRequestAttributes.java)

This example Spring Framework source code file (AbstractRequestAttributes.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Spring Framework tags/keywords

abstractrequestattributes, callback, iterator, linkedhashmap, linkedhashmap, map, map, name, name, requestattributes, runnable, runnable, util

The Spring Framework AbstractRequestAttributes.java source code

/*
 * Copyright 2002-2007 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
 *
 *      http://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.context.request;

import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.Map;

import org.springframework.util.Assert;

/**
 * Abstract support class for RequestAttributes implementations,
 * offering a request completion mechanism for request-specific destruction
 * callbacks and for updating accessed session attributes.
 *
 * @author Juergen Hoeller
 * @since 2.0
 * @see #requestCompleted()
 */
public abstract class AbstractRequestAttributes implements RequestAttributes {

	/** Map from attribute name String to destruction callback Runnable */
	protected final Map requestDestructionCallbacks = new LinkedHashMap(8);


	/**
	 * Signal that the request has been completed.
	 * <p>Executes all request destruction callbacks and updates the
	 * session attributes that have been accessed during request processing.
	 */
	public void requestCompleted() {
		executeRequestDestructionCallbacks();
		updateAccessedSessionAttributes();
	}

	/**
	 * Register the given callback as to be executed after request completion.
	 * @param name the name of the attribute to register the callback for
	 * @param callback the callback to be executed for destruction
	 */
	protected final void registerRequestDestructionCallback(String name, Runnable callback) {
		Assert.notNull(name, "Name must not be null");
		Assert.notNull(callback, "Callback must not be null");
		this.requestDestructionCallbacks.put(name, callback);
	}

	/**
	 * Remove the request destruction callback for the specified attribute, if any.
	 * @param name the name of the attribute to remove the callback for
	 */
	protected final void removeRequestDestructionCallback(String name) {
		Assert.notNull(name, "Name must not be null");
		this.requestDestructionCallbacks.remove(name);
	}

	/**
	 * Execute all callbacks that have been registered for execution
	 * after request completion.
	 */
	private void executeRequestDestructionCallbacks() {
		for (Iterator it = this.requestDestructionCallbacks.values().iterator(); it.hasNext();) {
			((Runnable) it.next()).run();
		}
		this.requestDestructionCallbacks.clear();
	}

	/**
	 * Update all session attributes that have been accessed during request processing,
	 * to expose their potentially updated state to the underlying session manager.
	 */
	protected abstract void updateAccessedSessionAttributes();

}