org.glassfish.hk2.api.Factory Maven / Gradle / Ivy
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* Copyright (c) 2012, 2018 Oracle and/or its affiliates. All rights reserved.
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v. 2.0, which is available at
* http://www.eclipse.org/legal/epl-2.0.
*
* This Source Code may also be made available under the following Secondary
* Licenses when the conditions for such availability set forth in the
* Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
* version 2 with the GNU Classpath Exception, which is available at
* https://www.gnu.org/software/classpath/license.html.
*
* SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
*/
package org.glassfish.hk2.api;
import org.jvnet.hk2.annotations.Contract;
/**
* This interface should be implemented in order to provide
* a factory for another type. This is useful when the type
* has some reason that it cannot be a created in the usual way.
*
* A factory may not have a TypeVariable or a Wildcard as its
* actual type. A factory may have any scope, and the scope
* of the factory is independent of the scope of the type it
* is providing.
*
* The scope and qualifiers of the objects this factory is producing
* must be placed on the provide method itself. Objects created with
* this method will be put into the scope on the provide method, and
* will have the qualifiers of the provide method.
*
* A factory is generally added with the {@link FactoryDescriptors} helper
* class, though factories can also be registered independently.
*
* A Factory implementation may inject a {@link InstantiationService}. If
* it does so then the {@link InstantiationService#getInstantiationData()} method
* will return information about the caller of the provide method if that
* information is available. This can be used to customize the returned object
* based on the Injection point of the parent.
*
* @author jwells
* @param This must be the type of entity for which this is a factory.
* For example, if this were a factory for Foo, then your factory
* must implement Factory<Foo>.
*
*/
@Contract
public interface Factory {
/**
* This method will create instances of the type of this factory. The provide
* method must be annotated with the desired scope and qualifiers.
*
* @return The produces object
*/
public T provide();
/**
* This method will dispose of objects created with this scope. This method should
* not be annotated, as it is naturally paired with the provide method
*
* @param instance The instance to dispose of
*/
public void dispose(T instance);
}