| /* |
| * Copyright 2014 Open Networking Laboratory |
| * |
| * 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.provider; |
| |
| import com.google.common.collect.ImmutableSet; |
| import org.onosproject.net.DeviceId; |
| |
| import java.util.HashMap; |
| import java.util.Map; |
| import java.util.Set; |
| |
| import static com.google.common.base.Preconditions.checkNotNull; |
| import static com.google.common.base.Preconditions.checkState; |
| |
| /** |
| * Base implementation of provider registry. |
| * |
| * @param <P> type of the information provider |
| * @param <S> type of the provider service |
| */ |
| public abstract class AbstractProviderRegistry<P extends Provider, S extends ProviderService<P>> |
| implements ProviderRegistry<P, S> { |
| |
| private final Map<ProviderId, P> providers = new HashMap<>(); |
| private final Map<ProviderId, S> services = new HashMap<>(); |
| private final Map<String, P> providersByScheme = new HashMap<>(); |
| |
| /** |
| * Creates a new provider service bound to the specified provider. |
| * |
| * @param provider provider |
| * @return provider service |
| */ |
| protected abstract S createProviderService(P provider); |
| |
| /** |
| * Returns the default fall-back provider. Default implementation return null. |
| * |
| * @return default provider |
| */ |
| protected P defaultProvider() { |
| return null; |
| } |
| |
| @Override |
| public synchronized S register(P provider) { |
| checkNotNull(provider, "Provider cannot be null"); |
| checkState(!services.containsKey(provider.id()), "Provider %s already registered", provider.id()); |
| |
| // If the provider is a primary one, check for a conflict. |
| ProviderId pid = provider.id(); |
| checkState(pid.isAncillary() || !providersByScheme.containsKey(pid.scheme()), |
| "A primary provider with id %s is already registered", |
| providersByScheme.get(pid.scheme())); |
| |
| S service = createProviderService(provider); |
| services.put(provider.id(), service); |
| providers.put(provider.id(), provider); |
| |
| // Register the provider by URI scheme only if it is not ancillary. |
| if (!pid.isAncillary()) { |
| providersByScheme.put(pid.scheme(), provider); |
| } |
| |
| return service; |
| } |
| |
| @Override |
| public synchronized void unregister(P provider) { |
| checkNotNull(provider, "Provider cannot be null"); |
| S service = services.get(provider.id()); |
| if (service != null && service instanceof AbstractProviderService) { |
| ((AbstractProviderService) service).invalidate(); |
| services.remove(provider.id()); |
| providers.remove(provider.id()); |
| if (!provider.id().isAncillary()) { |
| providersByScheme.remove(provider.id().scheme()); |
| } |
| } |
| } |
| |
| @Override |
| public synchronized Set<ProviderId> getProviders() { |
| return ImmutableSet.copyOf(services.keySet()); |
| } |
| |
| /** |
| * Returns the provider registered with the specified provider ID or null |
| * if none is found for the given provider family and default fall-back is |
| * not supported. |
| * |
| * @param providerId provider identifier |
| * @return provider |
| */ |
| protected synchronized P getProvider(ProviderId providerId) { |
| P provider = providers.get(providerId); |
| return provider != null ? provider : defaultProvider(); |
| } |
| |
| /** |
| * Returns the provider for the specified device ID based on URI scheme. |
| * |
| * @param deviceId device identifier |
| * @return provider bound to the URI scheme |
| */ |
| protected synchronized P getProvider(DeviceId deviceId) { |
| P provider = providersByScheme.get(deviceId.uri().getScheme()); |
| return provider != null ? provider : defaultProvider(); |
| } |
| |
| /** |
| * Returns the provider registered with the specified scheme. |
| * |
| * @param scheme provider scheme |
| * @return provider |
| */ |
| protected synchronized P getProvider(String scheme) { |
| return providersByScheme.get(scheme); |
| } |
| |
| } |