Spring Framework example source code file (AbstractRequestAttributesScope.java)

This example Spring Framework source code file (AbstractRequestAttributesScope.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

abstractrequestattributesscope, abstractrequestattributesscope, object, object, objectfactory, objectfactory, requestattributes, requestattributes, runnable, scope

The Spring Framework AbstractRequestAttributesScope.java source code

/*
 * Copyright 2002-2006 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 org.springframework.beans.factory.ObjectFactory;
import org.springframework.beans.factory.config.Scope;

/**
 * Abstract {@link Scope} implementation that reads from a particular scope
 * in the current thread-bound {@link RequestAttributes} object.
 *
 * <p>Subclasses simply need to implement {@link #getScope()} to instruct
 * this class which {@link RequestAttributes} scope to read attributes from.
 *
 * <p>Subclasses may wish to override the {@link #get} and {@link #remove}
 * methods to add synchronization around the call back into this super class.
 * 
 * @author Rod Johnson
 * @author Juergen Hoeller
 * @author Rob Harrop
 * @since 2.0
 */
public abstract class AbstractRequestAttributesScope implements Scope {

	public Object get(String name, ObjectFactory objectFactory) {
		RequestAttributes attributes = RequestContextHolder.currentRequestAttributes();
		Object scopedObject = attributes.getAttribute(name, getScope());
		if (scopedObject == null) {
			scopedObject = objectFactory.getObject();
			attributes.setAttribute(name, scopedObject, getScope());
		}
		return scopedObject;
	}

	public Object remove(String name) {
		RequestAttributes attributes = RequestContextHolder.currentRequestAttributes();
		Object scopedObject = attributes.getAttribute(name, getScope());
		if (scopedObject != null) {
			attributes.removeAttribute(name, getScope());
			return scopedObject;
		}
		else {
			return null;
		}
	}

	public void registerDestructionCallback(String name, Runnable callback) {
		RequestAttributes attributes = RequestContextHolder.currentRequestAttributes();
		attributes.registerDestructionCallback(name, callback, getScope());
	}


	/**
	 * Template method that determines the actual target scope.
	 * @return the target scope, in the form of an appropriate
	 * {@link RequestAttributes} constant
	 * @see RequestAttributes#SCOPE_REQUEST
	 * @see RequestAttributes#SCOPE_SESSION
	 * @see RequestAttributes#SCOPE_GLOBAL_SESSION
	 */
	protected abstract int getScope();

}