org.glassfish.hk2.api.IterableProvider Maven / Gradle / Ivy
/*
* 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 java.lang.annotation.Annotation;
import java.lang.reflect.Type;
import javax.inject.Provider;
/**
* This object can be injected rather than {@link Provider} when
* it is desired to iterate over more than one returned instance of the type.
* This interface also has several methods which allow the user to further
* narrow down the selected services at runtime. It can also provide
* an {@link Iterable} of {@link ServiceHandle} for finer control of the lifecycle
* of services found
*
* The iterator returned will be in ranked order (with DescriptorRank as
* primary key, largest rank first and ServiceID as secondary key, smallest
* id first)
*
* @author jwells
* @param The type of this IterableProvider
*/
public interface IterableProvider extends Provider, Iterable {
/**
* Rather than getting the service directly with get (in which
* case the returned service cannot be disposed of) this method
* will instead return a service handle for the current best service.
*
* @return A ServiceHandle for the service, or null if there is
* currently no service definition available
*/
public ServiceHandle getHandle();
/**
* Returns the size of the iterator that would be returned
*
* @return the size of the iterator that would be chosen
*/
public int getSize();
/**
* Returns an IterableProvider that is further qualified
* with the given name
*
* @param name The value field of the Named annotation parameter. Must
* not be null
* @return An iterable provider further qualified with the given name
*/
public IterableProvider named(String name);
/**
* Returns an IterableProvider that is of the given type. This type
* must be one of the type safe contracts of the original iterator
*
* @param type The type to restrict the returned iterator to
* @return An iterator restricted to only providing the given type
*/
public IterableProvider ofType(Type type);
/**
* A set of qualifiers to further restrict this iterator to.
*
* @param qualifiers The qualifiers to further restrict this iterator to
* @return An iterator restricted with the given qualifiers
*/
public IterableProvider qualifiedWith(Annotation... qualifiers);
/**
* This version of iterator returns an iterator of ServiceHandles rather
* than returning the services (which then have no way to be properly
* destroyed)
*
* @return An iterator of ServiceHandles for the set of services
* represtended by this IterableProvider
*/
public Iterable> handleIterator();
}