/*
* Copyright 2002-2009 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.context.support;
import java.util.HashMap;
import java.util.Map;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.beans.factory.ObjectFactory;
import org.springframework.beans.factory.config.Scope;
import org.springframework.core.NamedThreadLocal;
/**
* Thread-backed {@link Scope} implementation.
*
* <p><strong>Note</strong> that the <code>SimpleThreadScope</code> <em>does not clean up any objects</em> associated
* with it. As such, it's typically preferable to use the {@link org.springframework.web.context.request.RequestScope}
* in Web environments.
*
* <p>For a implementation of a thread-based <code>Scope</code> with support for destruction callbacks, refer to <a
* href="http://www.springbyexample.org/twiki/bin/view/Example/CustomThreadScopeModule">this module</a>.
*
* <p>Thanks to Eugene Kuleshov for submitting the original prototype for a thread scope!
*
* @author Arjen Poutsma
* @author Juergen Hoeller
* @since 3.0
* @see org.springframework.web.context.request.RequestScope
*/
public class SimpleThreadScope implements Scope {
private static final Log logger = LogFactory.getLog(SimpleThreadScope.class);
private final ThreadLocal<Map<String, Object>> threadScope =
new NamedThreadLocal<Map<String, Object>>("SimpleThreadScope") {
@Override
protected Map<String, Object> initialValue() {
return new HashMap<String, Object>();
}
};
public Object get(String name, ObjectFactory objectFactory) {
Map<String, Object> scope = threadScope.get();
Object object = scope.get(name);
if (object == null) {
object = objectFactory.getObject();
scope.put(name, object);
}
return object;
}
public Object remove(String name) {
Map<String, Object> scope = threadScope.get();
return scope.remove(name);
}
public void registerDestructionCallback(String name, Runnable callback) {
logger.warn("SimpleThreadScope does not support descruction callbacks. " +
"Consider using a RequestScope in a Web environment.");
}
public Object resolveContextualObject(String key) {
return null;
}
public String getConversationId() {
return Thread.currentThread().getName();
}
}
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