/**
    * 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
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  package org.apache.hadoop.hbase.util.compaction;
  
  import java.io.IOException;
  import java.util.Random;
  import com.google.common.collect.Sets;
  import org.apache.hadoop.hbase.HBaseTestingUtility;
  import org.apache.hadoop.hbase.TableName;
  import org.apache.hadoop.hbase.client.Connection;
  import org.apache.hadoop.hbase.client.HBaseAdmin;
  import org.apache.hadoop.hbase.client.Put;
  import org.apache.hadoop.hbase.client.Table;
  import org.apache.hadoop.hbase.testclassification.MediumTests;
  import org.apache.hadoop.hbase.testclassification.MiscTests;
  import org.apache.hadoop.hbase.util.Bytes;
  import org.junit.After;
  import static org.junit.Assert.assertEquals;
  import static org.junit.Assert.assertTrue;
  import org.junit.Before;
  import org.junit.Test;
  import org.junit.experimental.categories.Category;
  
  
  @Category({ MiscTests.class, MediumTests.class })
  public class MajorCompactorTest {
  
    public static final byte[] FAMILY = Bytes.toBytes("a");
    protected HBaseTestingUtility utility;
    protected HBaseAdmin admin;
  
    @Before public void setUp() throws Exception {
      utility = new HBaseTestingUtility();
      utility.getConfiguration().setInt("hbase.hfile.compaction.discharger.interval", 10);
      utility.startMiniCluster();
    }
  
    @After public void tearDown() throws Exception {
      utility.shutdownMiniCluster();
    }
  
    @Test public void testCompactingATable() throws Exception {
      TableName tableName = TableName.valueOf("MajorCompactorTest");
      utility.createMultiRegionTable(tableName, FAMILY, 5);
      utility.waitTableAvailable(tableName);
      Connection connection = utility.getConnection();
      Table table = connection.getTable(tableName);
      // write data and flush multiple store files:
      for (int i = 0; i < 5; i++) {
        loadRandomRows(table, FAMILY, 50, 100);
        utility.flush(tableName);
      }
      table.close();
      int numberOfRegions = utility.getHBaseAdmin().getTableRegions(tableName).size();
      int numHFiles = utility.getNumHFiles(tableName, FAMILY);
      // we should have a table with more store files than we would before we major compacted.
      assertTrue(numberOfRegions < numHFiles);
  
      MajorCompactor compactor =
          new MajorCompactor(utility.getConfiguration(), tableName,
              Sets.newHashSet(Bytes.toString(FAMILY)), 1, System.currentTimeMillis(), 200);
      compactor.initializeWorkQueues();
      compactor.compactAllRegions();
      compactor.shutdown();
  
      // verify that the store has been completely major compacted.
      numberOfRegions = utility.getHBaseAdmin().getTableRegions(tableName).size();
      numHFiles = utility.getNumHFiles(tableName, FAMILY);
      assertEquals(numHFiles, numberOfRegions);
    }
  
    protected void loadRandomRows(final Table t, final byte[] f, int rowSize, int totalRows)
        throws IOException {
      Random r = new Random();
      byte[] row = new byte[rowSize];
      for (int i = 0; i < totalRows; i++) {
        r.nextBytes(row);
        Put put = new Put(row);
        put.addColumn(f, new byte[]{0}, new byte[]{0});
        t.put(put);
      }
    }
  }