CellComparatorExample.java

package client;

// cc CellComparatorExample Shows how to use the cell scanner
import java.util.ArrayList;
import java.util.Collections;

import org.apache.hadoop.hbase.Cell;
import org.apache.hadoop.hbase.CellComparator;
import org.apache.hadoop.hbase.CellScanner;
import org.apache.hadoop.hbase.client.Put;
import org.apache.hadoop.hbase.util.Bytes;

public class CellComparatorExample {

  public static void main(String[] args) throws Exception {
    // vv CellComparatorExample
    Put put1 = new Put(Bytes.toBytes("row-1"));
    put1.addColumn(Bytes.toBytes("fam-1"), Bytes.toBytes("qual-1"),
      Bytes.toBytes("val-1"));
    Put put2 = new Put(Bytes.toBytes("row-2"));
    put2.addColumn(Bytes.toBytes("fam-1"), Bytes.toBytes("qual-2"),
      Bytes.toBytes("val-2"));
    Put put3 = new Put(Bytes.toBytes("row-3"));
    put3.addColumn(Bytes.toBytes("fam-2"), Bytes.toBytes("qual-3"),
      Bytes.toBytes("val-3"));
    Put put4 = new Put(Bytes.toBytes("row-1"));
    put4.addColumn(Bytes.toBytes("fam-2"), Bytes.toBytes("qual-2"),
      Bytes.toBytes("val-2"));

    CellComparator comparator = new CellComparator.RowComparator();
    ArrayList<Cell> cells = new ArrayList<>();

    Put[] puts = { put1, put2, put3, put4 };

    for (Put put : puts) {
      CellScanner scanner = put.cellScanner();
      while (scanner.advance()) {
        Cell cell = scanner.current();
        cells.add(cell);
      }
    }

    System.out.println("Shuffling...");
    Collections.shuffle(cells);
    for (Cell cell : cells) {
      System.out.println("Cell: " + cell);
    }

    System.out.println("Sorting...");
    Collections.sort(cells, comparator);
    for (Cell cell : cells) {
      System.out.println("Cell: " + cell);
    }
    // ^^ CellComparatorExample
  }
}