/*
* Copyright 2002-2008 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.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<String, Runnable> requestDestructionCallbacks = new LinkedHashMap<String, Runnable>(8);
private volatile boolean requestActive = true;
/**
* 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();
this.requestActive = false;
}
/**
* Determine whether the original request is still active.
* @see #requestCompleted()
*/
protected final boolean isRequestActive() {
return this.requestActive;
}
/**
* 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");
synchronized (this.requestDestructionCallbacks) {
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");
synchronized (this.requestDestructionCallbacks) {
this.requestDestructionCallbacks.remove(name);
}
}
/**
* Execute all callbacks that have been registered for execution
* after request completion.
*/
private void executeRequestDestructionCallbacks() {
synchronized (this.requestDestructionCallbacks) {
for (Runnable runnable : this.requestDestructionCallbacks.values()) {
runnable.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();
}
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