elb/src/main/java/org/jclouds/elb/binders/BindSubnetIdsToIndexedFormParams.java

/*
 * 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.elb.binders;

import static com.google.common.base.Preconditions.checkNotNull;

import javax.inject.Singleton;

import org.jclouds.http.HttpRequest;
import org.jclouds.rest.Binder;

import com.google.common.collect.ImmutableMultimap;
import com.google.common.collect.ImmutableMultimap.Builder;

/**
 * Binds the Iterable<String> to form parameters named with Subnets.member.index
 */
@Singleton
public class BindSubnetIdsToIndexedFormParams implements Binder {
   
   @SuppressWarnings("unchecked")
   @Override
   public <R extends HttpRequest> R bindToRequest(R request, Object input) {
      Iterable<?> values = Iterable.class.cast(checkNotNull(input, "subnetIds"));
      Builder<String, String> builder = ImmutableMultimap.builder();
      int i = 1;
      for (Object o : values) {
         builder.put("Subnets.member." + (i++), o.toString());
      }
      ImmutableMultimap<String, String> forms = builder.build();
      return (R) (forms.size() == 0 ? request : request.toBuilder().replaceFormParams(forms).build());
   }

}