Java tutorial
/** * Licensed to jclouds, Inc. (jclouds) under one or more * contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. jclouds 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.rackspace.cloudloadbalancers.functions; import static com.google.common.base.Preconditions.checkNotNull; import static com.google.common.base.Preconditions.checkState; import java.util.Map; import javax.inject.Inject; import org.jclouds.http.HttpRequest; import org.jclouds.http.HttpResponse; import org.jclouds.http.functions.ParseJson; import org.jclouds.rackspace.cloudloadbalancers.domain.LoadBalancer; import org.jclouds.rackspace.cloudloadbalancers.functions.ConvertLB.Factory; import org.jclouds.rest.InvocationContext; import com.google.common.base.Function; import com.google.common.collect.Iterables; /** * @author Adrian Cole */ public class ParseLoadBalancer implements Function<HttpResponse, LoadBalancer>, InvocationContext<ParseLoadBalancer> { private final ParseJson<Map<String, LB>> json; private final Factory factory; private ConvertLB convertLB; @Inject ParseLoadBalancer(ParseJson<Map<String, LB>> json, ConvertLB.Factory factory) { this.json = checkNotNull(json, "json"); this.factory = checkNotNull(factory, "factory"); } @Override public LoadBalancer apply(HttpResponse arg0) { checkState(convertLB != null, "convertLB should be set by InvocationContext"); Map<String, LB> map = json.apply(arg0); if (map == null || map.size() == 0) return null; LB lb = Iterables.get(map.values(), 0); return convertLB.apply(lb); } @Override public ParseLoadBalancer setContext(HttpRequest request) { return setRegion( request.getEndpoint().getHost().substring(0, request.getEndpoint().getHost().indexOf('.'))); } ParseLoadBalancer setRegion(String region) { this.convertLB = factory.createForRegion(region); return this; } }