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.service.paxos.cleanup;
  
  import java.io.IOException;
  import java.util.Collection;
  import java.util.HashSet;
  import java.util.Set;
  
  import org.apache.cassandra.db.TypeSizes;
  import org.apache.cassandra.exceptions.RequestFailure;
  import org.apache.cassandra.io.IVersionedSerializer;
  import org.apache.cassandra.io.util.DataInputPlus;
  import org.apache.cassandra.io.util.DataOutputPlus;
  import org.apache.cassandra.locator.InetAddressAndPort;
  import org.apache.cassandra.net.IVerbHandler;
  import org.apache.cassandra.net.Message;
  import org.apache.cassandra.net.RequestCallbackWithFailure;
  import org.apache.cassandra.repair.SharedContext;
  import org.apache.cassandra.service.accord.IAccordService;
  import org.apache.cassandra.service.paxos.Ballot;
  import org.apache.cassandra.service.paxos.Ballot.Flag;
  import org.apache.cassandra.service.paxos.PaxosState;
  import org.apache.cassandra.utils.concurrent.AsyncFuture;
  
  import static com.google.common.base.Preconditions.checkArgument;
  import static org.apache.cassandra.net.NoPayload.noPayload;
  import static org.apache.cassandra.net.Verb.PAXOS2_UPDATE_LOW_BALLOT_REQ;
  
  public class PaxosUpdateLowBallot extends AsyncFuture<Void> implements RequestCallbackWithFailure<Void>
  {
      private final Set<InetAddressAndPort> waitingResponse;
      private final long lowBound;
      private final SharedContext ctx;
  
      public PaxosUpdateLowBallot(SharedContext ctx, Collection<InetAddressAndPort> endpoints, long maxHlc)
      {
          checkArgument(maxHlc != IAccordService.NO_HLC);
          this.ctx = ctx;
          this.waitingResponse = new HashSet<>(endpoints);
          this.lowBound = maxHlc + 1;
      }
  
      public synchronized void start()
      {
          Request request = new Request(lowBound);
  
          Message<Request> message = Message.out(PAXOS2_UPDATE_LOW_BALLOT_REQ, request);
  
          for (InetAddressAndPort endpoint : waitingResponse)
              ctx.messaging().sendWithCallback(message, endpoint, this);
      }
  
      @Override
      public void onFailure(InetAddressAndPort from, RequestFailure reason)
      {
          tryFailure(new PaxosCleanupException("Timed out waiting on response from " + from));
      }
  
      @Override
      public synchronized void onResponse(Message<Void> msg)
      {
          if (isDone())
              return;
  
          if (!waitingResponse.remove(msg.from()))
              throw new IllegalArgumentException("Received unexpected response from " + msg.from());
  
          if (waitingResponse.isEmpty())
              trySuccess(null);
      }
  
      public static class Request
      {
          final long lowBound;
  
          Request(long lowBound)
          {
              this.lowBound = lowBound;
          }
      }
  
      public static final IVersionedSerializer<Request> serializer = new IVersionedSerializer<Request>()
      {
          public void serialize(Request request, DataOutputPlus out, int version) throws IOException
          {
              out.writeLong(request.lowBound);
          }
  
          public Request deserialize(DataInputPlus in, int version) throws IOException
          {
              return new Request(in.readLong());
          }
  
          public long serializedSize(Request request, int version)
          {
              return TypeSizes.sizeof(request.lowBound);
          }
      };
  
      public static IVerbHandler<Request> createVerbHandler(SharedContext ctx)
      {
          return (in) -> {
              PaxosState.ballotTracker().updateLowBound(Ballot.atUnixMicrosWithLsb(in.payload.lowBound, 0, Flag.GLOBAL));
              ctx.messaging().respond(noPayload, in);
          };
      }
  
      public static final IVerbHandler<Request> verbHandler = createVerbHandler(SharedContext.Global.instance);
  }
  