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
   *
   *   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.apache.asterix.metadata.entities;
  
  import java.util.ArrayList;
  import java.util.Collection;
  import java.util.Collections;
  import java.util.List;
  
  import org.apache.asterix.metadata.MetadataCache;
  import org.apache.asterix.metadata.api.IMetadataEntity;
  
  /**
   * Metadata describing a named group of compute nodes.
   */
  public class NodeGroup implements IMetadataEntity<NodeGroup> {
  
      private static final long serialVersionUID = 1L;
  
      // Enforced to be unique within an Asterix cluster.
      private final String groupName;
      private final List<String> nodeNames;
  
      public NodeGroup(String groupName, List<String> nodeNames) {
          this.groupName = groupName;
          this.nodeNames = nodeNames;
      }
  
      public static NodeGroup createOrdered(String groupName, Collection<String> nodeNames) {
          List<String> sortedNodeNames = new ArrayList<>(nodeNames);
          Collections.sort(sortedNodeNames);
          return new NodeGroup(groupName, sortedNodeNames);
      }
  
      public String getNodeGroupName() {
          return this.groupName;
      }
  
      public List<String> getNodeNames() {
          return Collections.unmodifiableList(new ArrayList<>(nodeNames));
      }
  
      @Override
      public NodeGroup addToCache(MetadataCache cache) {
          return cache.addOrUpdateNodeGroup(this);
      }
  
      @Override
      public NodeGroup dropFromCache(MetadataCache cache) {
          return cache.dropNodeGroup(this);
      }
  }
  