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.gms;
  
  import java.net.InetAddress;
  import java.net.UnknownHostException;
  import java.util.Collections;
  import java.util.EnumMap;
  import java.util.List;
  import java.util.Map;
  import java.util.Set;
  import java.util.UUID;
  import java.util.concurrent.atomic.AtomicInteger;
  
  import org.junit.BeforeClass;
  import org.junit.Test;
  
  import org.apache.cassandra.config.DatabaseDescriptor;
  import org.apache.cassandra.dht.Token;
  
  import static org.junit.Assert.assertEquals;
  import static org.junit.Assert.assertTrue;
  
  public class EndpointStateTest
  {
      public volatile VersionedValue.VersionedValueFactory valueFactory =
          new VersionedValue.VersionedValueFactory(DatabaseDescriptor.getPartitioner());
  
      @BeforeClass
      public static void setupDD()
      {
          DatabaseDescriptor.daemonInitialization();
      }
  
      @Test
      public void testMultiThreadedReadConsistency() throws InterruptedException
      {
          for (int i = 0; i < 500; i++)
              innerTestMultiThreadedReadConsistency();
      }
  
      /**
       * Test that a thread reading values whilst they are updated by another thread will
       * not see an entry unless it sees the entry previously added as well, even though
       * we are accessing the map via an iterator backed by the underlying map. This
       * works because EndpointState copies the map each time values are added.
       */
      private void innerTestMultiThreadedReadConsistency() throws InterruptedException
      {
          final Token token = DatabaseDescriptor.getPartitioner().getRandomToken();
          final List<Token> tokens = Collections.singletonList(token);
          final HeartBeatState hb = new HeartBeatState(0);
          final EndpointState state = new EndpointState(hb);
          final AtomicInteger numFailures = new AtomicInteger();
  
          Thread t1 = new Thread(new Runnable()
          {
              public void run()
              {
                  state.addApplicationState(ApplicationState.TOKENS, valueFactory.tokens(tokens));
                  state.addApplicationState(ApplicationState.STATUS_WITH_PORT, valueFactory.normal(tokens));
              }
          });
  
          Thread t2 = new Thread(new Runnable()
          {
              public void run()
              {
                  for (int i = 0; i < 50; i++)
                  {
                      Map<ApplicationState, VersionedValue> values = new EnumMap<>(ApplicationState.class);
                      for (Map.Entry<ApplicationState, VersionedValue> entry : state.states())
                          values.put(entry.getKey(), entry.getValue());
  
                      if (values.containsKey(ApplicationState.STATUS_WITH_PORT) && !values.containsKey(ApplicationState.TOKENS))
                      {
                          numFailures.incrementAndGet();
                          System.out.println(String.format("Failed: %s", values));
                      }
                  }
              }
          });
  
          t1.start();
          t2.start();
  
          t1.join();
          t2.join();
  
          assertTrue(numFailures.get() == 0);
      }
  
      @Test
      public void testMultiThreadWriteConsistency() throws InterruptedException, UnknownHostException
      {
          for (int i = 0; i < 500; i++)
              innerTestMultiThreadWriteConsistency();
      }
  
      /**
       * Test that two threads can update the state map concurrently.
       */
      private void innerTestMultiThreadWriteConsistency() throws InterruptedException, UnknownHostException
      {
          final Token token = DatabaseDescriptor.getPartitioner().getRandomToken();
          final List<Token> tokens = Collections.singletonList(token);
          final InetAddress ip = InetAddress.getByAddress(null, new byte[] { 127, 0, 0, 1});
          final UUID hostId = UUID.randomUUID();
          final HeartBeatState hb = new HeartBeatState(0);
          final EndpointState state = new EndpointState(hb);
  
          Thread t1 = new Thread(new Runnable()
          {
              public void run()
              {
                  Map<ApplicationState, VersionedValue> states = new EnumMap<>(ApplicationState.class);
                  states.put(ApplicationState.TOKENS, valueFactory.tokens(tokens));
                  states.put(ApplicationState.STATUS_WITH_PORT, valueFactory.normal(tokens));
                  state.addApplicationStates(states);
              }
          });
  
          Thread t2 = new Thread(new Runnable()
          {
              public void run()
              {
                  Map<ApplicationState, VersionedValue> states = new EnumMap<>(ApplicationState.class);
                  states.put(ApplicationState.INTERNAL_IP, valueFactory.internalIP(ip));
                  states.put(ApplicationState.HOST_ID, valueFactory.hostId(hostId));
                  state.addApplicationStates(states);
              }
          });
  
          t1.start();
          t2.start();
  
          t1.join();
          t2.join();
  
          Set<Map.Entry<ApplicationState, VersionedValue>> states = state.states();
          assertEquals(4, states.size());
  
          Map<ApplicationState, VersionedValue> values = new EnumMap<>(ApplicationState.class);
          for (Map.Entry<ApplicationState, VersionedValue> entry : states)
              values.put(entry.getKey(), entry.getValue());
  
          assertTrue(values.containsKey(ApplicationState.STATUS_WITH_PORT));
          assertTrue(values.containsKey(ApplicationState.TOKENS));
          assertTrue(values.containsKey(ApplicationState.INTERNAL_IP));
          assertTrue(values.containsKey(ApplicationState.HOST_ID));
      }
  }
  