runtime/common/src/main/java/org/apache/nemo/runtime/common/message/ncs/NcsMessageContext.java

/*
 * 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.nemo.runtime.common.message.ncs;

import org.apache.nemo.runtime.common.message.MessageContext;
import org.apache.reef.exception.evaluator.NetworkException;
import org.apache.reef.io.network.Connection;
import org.apache.reef.io.network.ConnectionFactory;
import org.apache.reef.wake.IdentifierFactory;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * Message context for NCS.
 */
final class NcsMessageContext implements MessageContext {
  private static final Logger LOG = LoggerFactory.getLogger(NcsMessageContext.class.getName());

  private final String senderId;
  private final ConnectionFactory connectionFactory;
  private final IdentifierFactory idFactory;

  NcsMessageContext(final String senderId,
                    final ConnectionFactory connectionFactory,
                    final IdentifierFactory idFactory) {
    this.senderId = senderId;
    this.connectionFactory = connectionFactory;
    this.idFactory = idFactory;
  }

  public String getSenderId() {
    return senderId;
  }

  @Override
  @SuppressWarnings("squid:S2095")
  public <U> void reply(final U replyMessage) {
    final Connection connection = connectionFactory.newConnection(idFactory.getNewInstance(senderId));
    try {
      connection.open();
      connection.write(replyMessage);
      // We do not call connection.close since NCS caches connection.
      // Disabling Sonar warning (squid:S2095)
    } catch (final NetworkException e) {
      // TODO #140: Properly classify and handle each RPC failure
      // Not logging the stacktrace here, as it's not very useful.
      LOG.error("NCS Exception");
    }
  }
}