javax.enterprise.context.spi.Context Maven / Gradle / Ivy
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* Licensed to the Apache Software Foundation (ASF) under one
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* distributed with this work for additional information
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* to you 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 javax.enterprise.context.spi;
import java.lang.annotation.Annotation;
import javax.enterprise.context.ContextNotActiveException;
import javax.enterprise.context.NormalScope;
/**
* Every webbeans component has an associated context that are
* defined by the {@link NormalScope} annotation. Webbeans components
* that are contained in the context are managed by the webbeans container.
*
*
* Every context has a well-defined lifecycle. It means that
* in some time, context is active and some other time context may
* be passive. Moreover, each context is created and destroyed by the container
* according to the timing requirements. For example, request context is started by every
* http request and destroyed at the end of the http response. According to the current thread,
* active context is called an thread current context.
*
*
*
* Context is responsible for creating and destroying the {@link Contextual} instances of the
* webbeans components.
*
*
* @version $Rev: 1796096 $ $Date: 2017-05-24 16:27:18 -0400 (Wed, 24 May 2017) $
*/
public interface Context
{
/**
* Returns the scope type of the context.
*
* @return the scope type of the context
*/
Class getScope();
/**
* If the context is not active, throws {@link ContextNotActiveException}.
* Otherwise, it looks for the given component instance in the context map. If
* this context contains the given webbeans component instance, it returns the component.
* If the component is not found in this context map, it looks for the creationalContext
* argument. If it is null, it returns null, otherwise new webbeans instance is created
* and puts into the context and returns it.
*
* @param type of the webbeans component
* @param component webbeans component
* @param creationalContext {@link CreationalContext} instance
* @return the contextual instance or null
*/
T get(Contextual component, CreationalContext creationalContext);
/**
* Returns the instance of the webbeans in this context if exist otherwise return null.
*
* @param type of the webbeans component
* @param component webbeans component
* @return the instance of the webbeans in this context if exist otherwise return null
*/
T get(Contextual component);
/**
* Returns true if context is active according to the current thread,
* returns false otherwise.
*
* @return true if context is active according to the current thread,
* return false otherwise
*/
boolean isActive();
}