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.hive.service;
  
  import org.apache.hadoop.hive.conf.HiveConf;
  import org.apache.hive.service.Service.STATE;
  
  /**
   * This is a service that can be configured to break on any of the lifecycle
   * events, so test the failure handling of other parts of the service
   * infrastructure.
   *
   * It retains a counter to the number of times each entry point is called -
   * these counters are incremented before the exceptions are raised and
   * before the superclass state methods are invoked.
   *
   */
  public class BreakableService extends AbstractService {
    private boolean failOnInit;
    private boolean failOnStart;
    private boolean failOnStop;
    private final int[] counts = new int[4];
  
    public BreakableService() {
      this(false, false, false);
    }
  
    public BreakableService(boolean failOnInit,
                            boolean failOnStart,
                            boolean failOnStop) {
      super("BreakableService");
      this.failOnInit = failOnInit;
      this.failOnStart = failOnStart;
      this.failOnStop = failOnStop;
      inc(STATE.NOTINITED);
    }
  
    private int convert(STATE state) {
      switch (state) {
        case NOTINITED: return 0;
        case INITED:    return 1;
        case STARTED:   return 2;
        case STOPPED:   return 3;
        default:        return 0;
      }
    }
  
    private void inc(STATE state) {
      int index = convert(state);
      counts[index] ++;
    }
  
    public int getCount(STATE state) {
      return counts[convert(state)];
    }
  
    private void maybeFail(boolean fail, String action) {
      if (fail) {
        throw new BrokenLifecycleEvent(action);
      }
    }
  
    @Override
    public void init(HiveConf conf) {
      inc(STATE.INITED);
      maybeFail(failOnInit, "init");
      super.init(conf);
    }
  
    @Override
    public void start() {
      inc(STATE.STARTED);
      maybeFail(failOnStart, "start");
      super.start();
    }
  
    @Override
    public void stop() {
      inc(STATE.STOPPED);
      maybeFail(failOnStop, "stop");
      super.stop();
    }
  
    public void setFailOnInit(boolean failOnInit) {
      this.failOnInit = failOnInit;
    }
  
    public void setFailOnStart(boolean failOnStart) {
      this.failOnStart = failOnStart;
    }
  
    public void setFailOnStop(boolean failOnStop) {
      this.failOnStop = failOnStop;
    }
  
    /**
     * The exception explicitly raised on a failure
     */
    public static class BrokenLifecycleEvent extends RuntimeException {
      BrokenLifecycleEvent(String action) {
        super("Lifecycle Failure during " + action);
      }
    }
  
  }
  