| /* |
| * 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.optical.device.port; |
| |
| import java.util.Optional; |
| |
| import org.onosproject.net.Port; |
| |
| import com.google.common.annotations.Beta; |
| import com.google.common.cache.CacheBuilder; |
| import com.google.common.cache.CacheLoader; |
| import com.google.common.cache.LoadingCache; |
| |
| /** |
| * PortMapper which caches mapped Port instance. |
| */ |
| @Beta |
| public abstract class AbstractPortMapper<P extends Port> implements PortMapper<P> { |
| |
| private final LoadingCache<Port, Optional<P>> cache |
| = CacheBuilder.newBuilder() |
| .weakKeys() // use == to compare keys |
| .maximumSize(100) |
| .build(CacheLoader.from(this::mapPort)); |
| |
| /** |
| * {@inheritDoc} |
| * |
| * <p> |
| * Note: Subclasses should override and implement short-cut conditions |
| * and call {@code super.is(port)}. |
| */ |
| @Override |
| public boolean is(Port port) { |
| return as(port).isPresent(); |
| } |
| |
| /** |
| * {@inheritDoc} |
| * |
| * <p> |
| * Note: Subclasses should override and check if {@code port} is |
| * already of type {@code P} and directly return {@code Optional.of((P) port)}, |
| * if not call {@code super.as(port)}. |
| */ |
| @Override |
| public Optional<P> as(Port port) { |
| if (port == null) { |
| return Optional.empty(); |
| } |
| return cache.getUnchecked(port); |
| } |
| |
| /** |
| * Returns {@code port} mapped to {@code <P>}. |
| * |
| * @param port Port to map |
| * @return {@code port} mapped to {@code <P>} |
| */ |
| protected abstract Optional<P> mapPort(Port port); |
| |
| } |