core/src/main/java/org/jclouds/ohai/config/multibindings/RealElement.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.ohai.config.multibindings;

import java.lang.annotation.Annotation;
import java.util.concurrent.atomic.AtomicInteger;

/**
 * @author jessewilson@google.com (Jesse Wilson)
 */
class RealElement implements Element {
   private static final AtomicInteger nextUniqueId = new AtomicInteger(1);

   private final int uniqueId;
   private final String setName;

   RealElement(String setName) {
      uniqueId = nextUniqueId.getAndIncrement();
      this.setName = setName;
   }

   public String setName() {
      return setName;
   }

   public int uniqueId() {
      return uniqueId;
   }

   public Class<? extends Annotation> annotationType() {
      return Element.class;
   }

   @Override
   public String toString() {
      return "@" + Element.class.getName() + "(setName=" + setName + ",uniqueId=" + uniqueId + ")";
   }

   @Override
   public boolean equals(Object o) {
      return o instanceof Element && ((Element) o).setName().equals(setName())
            && ((Element) o).uniqueId() == uniqueId();
   }

   @Override
   public int hashCode() {
      return 127 * ("setName".hashCode() ^ setName.hashCode()) + 127 * ("uniqueId".hashCode() ^ uniqueId);
   }
}