content: /**
   * 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
   * <p>
   * http://www.apache.org/licenses/LICENSE-2.0
   * <p>
   * 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.apache.atlas.util;
  
  import org.apache.atlas.v1.model.instance.Referenceable;
  
  import java.util.Collection;
  import java.util.HashMap;
  import java.util.HashSet;
  import java.util.Map;
  import java.util.Set;
  
  /**
   * Map of attribute values to a collection of IndexedInstances with that attribute value.
   *
   */
  public class AttributeValueMap {
      //need collection in case they are adding the same entity twice?
      private final Map<Object, Collection<IndexedInstance>> valueMap = new HashMap<>();
  
      public void put(Object value, Referenceable instance, int index) {
          IndexedInstance             wrapper        = new IndexedInstance(instance, index);
          Collection<IndexedInstance> existingValues = valueMap.computeIfAbsent(value, k -> new HashSet<>(1)); // only expect 1 value
  
          existingValues.add(wrapper);
      }
  
      public Collection<IndexedInstance> get(Object value) {
          return valueMap.get(value);
      }
  
      public Set<Object> getAttributeValues() {
          return valueMap.keySet();
      }
  }
  