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    * 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
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    * 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,
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   * See the License for the specific language governing permissions and
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  package org.apache.hadoop.hbase.chaos.actions;
  
  import org.apache.hadoop.hbase.HBaseTestingUtility;
  import org.apache.hadoop.hbase.HConstants;
  import org.apache.hadoop.hbase.HTableDescriptor;
  import org.apache.hadoop.hbase.TableName;
  import org.apache.hadoop.hbase.client.Admin;
  
  import java.util.Random;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  public class DecreaseMaxHFileSizeAction extends Action {
    private static final Logger LOG = LoggerFactory.getLogger(DecreaseMaxHFileSizeAction.class);
  
    private static final long minFileSize = 1024 * 1024 * 1024L;
  
    private final long sleepTime;
    private final TableName tableName;
    private final Random random;
  
    public DecreaseMaxHFileSizeAction(long sleepTime, TableName tableName) {
      this.sleepTime = sleepTime;
      this.tableName = tableName;
      this.random = new Random();
    }
  
    @Override protected Logger getLogger() {
      return LOG;
    }
  
    @Override
    public void perform() throws Exception {
      HBaseTestingUtility util = context.getHBaseIntegrationTestingUtility();
      Admin admin = util.getHBaseAdmin();
      HTableDescriptor htd = admin.getTableDescriptor(tableName);
  
      // Try and get the current value.
      long currentValue = htd.getMaxFileSize();
  
      // If the current value is not set use the default for the cluster.
      // If configs are really weird this might not work.
      // That's ok. We're trying to cause chaos.
      if (currentValue <= 0) {
        currentValue =
            context.getHBaseCluster().getConf().getLong(HConstants.HREGION_MAX_FILESIZE,
                HConstants.DEFAULT_MAX_FILE_SIZE);
      }
  
      // Decrease by 10% at a time.
      long newValue = (long) (currentValue * 0.9);
  
      // We don't want to go too far below 1gb.
      // So go to about 1gb +/- 512 on each side.
      newValue = Math.max(minFileSize, newValue) - (512 - random.nextInt(1024));
  
      // Change the table descriptor.
      htd.setMaxFileSize(newValue);
  
      // Don't try the modify if we're stopping
      if (context.isStopping()) {
        return;
      }
  
      // modify the table.
      admin.modifyTable(tableName, htd);
  
      // Sleep some time.
      if (sleepTime > 0) {
        Thread.sleep(sleepTime);
      }
    }
  }