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.ambari.server.agent;
  
  import java.util.ArrayList;
  import java.util.List;
  import java.util.concurrent.ExecutorService;
  import java.util.concurrent.Executors;
  import java.util.concurrent.ThreadFactory;
  
  import org.apache.ambari.server.AmbariException;
  import org.apache.ambari.server.configuration.Configuration;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import com.google.common.util.concurrent.ThreadFactoryBuilder;
  import com.google.inject.Inject;
  import com.google.inject.Singleton;
  import com.google.inject.persist.UnitOfWork;
  
  @Singleton
  public class AgentReportsProcessor {
    private static final Logger LOG = LoggerFactory.getLogger(AgentReportsProcessor.class);
  
    private final int poolSize;
  
    private final List<ExecutorService> executors;
  
    public void addAgentReport(AgentReport agentReport) {
      int hash = agentReport.getHostName().hashCode();
      hash = hash == Integer.MIN_VALUE ? 0 : hash;
      int executorNumber = Math.abs(hash) % poolSize;
      executors.get(executorNumber).execute(new AgentReportProcessingTask(agentReport));
    }
  
    @Inject
    private UnitOfWork unitOfWork;
  
    @Inject
    public AgentReportsProcessor(Configuration configuration) {
  
      ThreadFactory threadFactory = new ThreadFactoryBuilder().setNameFormat("agent-report-processor-%d").build();
      poolSize = configuration.getAgentsReportThreadPoolSize();
      executors = new ArrayList<>();
      for (int i = 0; i < poolSize; i++) {
        executors.add(Executors.newSingleThreadExecutor(threadFactory));
      }
    }
  
    private class AgentReportProcessingTask implements Runnable {
  
      private final AgentReport agentReport;
  
      public AgentReportProcessingTask(AgentReport agentReport) {
        this.agentReport = agentReport;
      }
  
      @Override
      public void run() {
        try {
          unitOfWork.begin();
          try {
            agentReport.process();
          } catch (AmbariException e) {
            LOG.error("Error processing agent reports", e);
          }
        } finally {
          unitOfWork.end();
        }
      }
    }
  }
  