| /* |
| * Copyright 2016-present Open Networking Foundation |
| * |
| * 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.onosproject.net.driver; |
| |
| import java.util.Optional; |
| |
| import com.google.common.annotations.Beta; |
| |
| /** |
| * Abstraction of an entity capable of being projected as another entity. |
| */ |
| @Beta |
| public interface Projectable { |
| |
| /** |
| * Returns the specified projection of this entity if such projection |
| * is supported. |
| * |
| * @param projectionClass requested projection class |
| * @param <B> type of behaviour |
| * @return projection instance |
| * @throws IllegalStateException if a driver cannot be found |
| * @throws IllegalArgumentException if the projection is not supported |
| */ |
| <B extends Behaviour> B as(Class<B> projectionClass); |
| |
| /** |
| * Returns true if this entity is capable of being projected as the |
| * specified class. |
| * |
| * @param projectionClass requested projection class |
| * @param <B> type of behaviour |
| * @return true if the requested projection is supported |
| */ |
| <B extends Behaviour> boolean is(Class<B> projectionClass); |
| |
| /** |
| * Returns the specified projection of this entity if such projection |
| * is supported. |
| * |
| * @param projectionClass requested projection class |
| * @param <B> type of behaviour |
| * @return projection instance |
| */ |
| default <B extends Behaviour> Optional<B> project(Class<B> projectionClass) { |
| if (is(projectionClass)) { |
| return Optional.of(as(projectionClass)); |
| } else { |
| return Optional.empty(); |
| } |
| } |
| |
| } |