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.cassandra.locator;
  
  import java.util.function.Predicate;
  
  import static org.apache.cassandra.config.DatabaseDescriptor.getLocalDataCenter;
  import static org.apache.cassandra.config.DatabaseDescriptor.getLocator;
  
  public class InOurDc
  {
      private static ReplicaTester replicas;
      private static EndpointTester endpoints;
  
      final String dc;
      final Locator locator;
  
      private InOurDc(String dc, Locator locator)
      {
          this.dc = dc;
          this.locator = locator;
      }
  
      boolean stale()
      {
          return !dc.equals(getLocalDataCenter());
      }
  
      private static final class ReplicaTester extends InOurDc implements Predicate<Replica>
      {
          private ReplicaTester(String dc, Locator locator)
          {
              super(dc, locator);
          }
  
          @Override
          public boolean test(Replica replica)
          {
              return dc.equals(locator.location(replica.endpoint()).datacenter);
          }
      }
  
      private static final class EndpointTester extends InOurDc implements Predicate<InetAddressAndPort>
      {
          private EndpointTester(String dc, Locator locator)
          {
              super(dc, locator);
          }
  
          @Override
          public boolean test(InetAddressAndPort endpoint)
          {
              return dc.equals(locator.location(endpoint).datacenter);
          }
      }
  
      public static Predicate<Replica> replicas()
      {
          ReplicaTester cur = replicas;
          if (cur == null || cur.stale())
              replicas = cur = new ReplicaTester(getLocalDataCenter(), getLocator());
          return cur;
      }
  
      public static Predicate<InetAddressAndPort> endpoints()
      {
          EndpointTester cur = endpoints;
          if (cur == null || cur.stale())
              endpoints = cur = new EndpointTester(getLocalDataCenter(), getLocator());
          return cur;
      }
  
      public static boolean isInOurDc(Replica replica)
      {
          return replicas().test(replica);
      }
  
      public static boolean isInOurDc(InetAddressAndPort endpoint)
      {
          return endpoints().test(endpoint);
      }
  
  }
  