Java tutorial
/* * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You 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.jclouds.openstack.keystone.v1_1.suppliers; import static com.google.common.collect.Iterables.tryFind; import java.util.NoSuchElementException; import javax.inject.Inject; import javax.inject.Singleton; import org.jclouds.location.suppliers.ImplicitRegionIdSupplier; import org.jclouds.openstack.keystone.v1_1.domain.Auth; import org.jclouds.openstack.keystone.v1_1.domain.Endpoint; import org.jclouds.openstack.keystone.v1_1.functions.EndpointToRegion; import com.google.common.base.Optional; import com.google.common.base.Predicate; import com.google.common.base.Supplier; import com.google.common.collect.Iterables; import com.google.inject.assistedinject.Assisted; @Singleton public class V1DefaultRegionIdSupplier implements ImplicitRegionIdSupplier { public static interface Factory { /** * * @param apiType * type of the api, according to the provider. ex. {@code compute} * {@code object-store} * @return region id * @throws NoSuchElementException * if the {@code apiType} is not present in the catalog */ ImplicitRegionIdSupplier createForApiType(@Assisted("apiType") String apiType) throws NoSuchElementException; } private final Supplier<Auth> auth; private final EndpointToRegion endpointToRegion; private final String apiType; @Inject public V1DefaultRegionIdSupplier(Supplier<Auth> auth, EndpointToRegion endpointToRegion, @Assisted("apiType") String apiType) { this.auth = auth; this.endpointToRegion = endpointToRegion; this.apiType = apiType; } /** * returns {@link Endpoint#isV1Default()} or first endpoint for service */ @Override public String get() { Auth authResponse = auth.get(); Iterable<Endpoint> endpointsForService = authResponse.getServiceCatalog().get(apiType); Optional<Endpoint> defaultEndpoint = tryFind(endpointsForService, new Predicate<Endpoint>() { @Override public boolean apply(Endpoint in) { return in.isV1Default(); } }); return endpointToRegion.apply(defaultEndpoint.or(Iterables.get(endpointsForService, 0))); } @Override public String toString() { return "defaultRegionIdFor(" + apiType + ")"; } }