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 com.alibaba.wasp.master.balancer;
  
  import com.alibaba.wasp.master.FMaster;
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  import org.apache.hadoop.hbase.Chore;
  
  import java.io.IOException;
  
  /**
   * Chore that will call FMaster.balance{@link org.apache.wap.master.FMaster#balance()} when
   * needed.
   */
  public class BalancerChore extends Chore {
    private static final Log LOG = LogFactory.getLog(BalancerChore.class);
    private final FMaster master;
  
    public BalancerChore(FMaster master) {
      super(master.getServerName() + "-BalancerChore",
          master.getConfiguration().getInt("wasp.balancer.period", 300000),
          master);
      this.master = master;
    }
  
    @Override
    protected void chore() {
      try {
        master.balance();
      } catch (IOException ioe) {
        LOG.error("Error invoking balancer", ioe);
      }
    }
  }
  