HbaseDependentColumnFilter

尝试找到该列所在的每一行，并返回该行具有相同时间戳的全部键值对。如果某一行不包含指定的列，则该行的任何键值对都不返回。
如果dropDependentColumn=true，则从属列不返回。

via: http://abloz.com/2012/08/22/the-hbases-content-query-2.html

package com.fatkun.filter.comparison;
import java.io.IOException;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.HBaseConfiguration;
import org.apache.hadoop.hbase.HColumnDescriptor;
import org.apache.hadoop.hbase.HTableDescriptor;
import org.apache.hadoop.hbase.KeyValue;
import org.apache.hadoop.hbase.client.Get;
import org.apache.hadoop.hbase.client.HBaseAdmin;
import org.apache.hadoop.hbase.client.HTable;
import org.apache.hadoop.hbase.client.Put;
import org.apache.hadoop.hbase.client.Result;
import org.apache.hadoop.hbase.client.ResultScanner;
import org.apache.hadoop.hbase.client.Scan;
import org.apache.hadoop.hbase.filter.BinaryPrefixComparator;
import org.apache.hadoop.hbase.filter.CompareFilter;
import org.apache.hadoop.hbase.filter.DependentColumnFilter;
import org.apache.hadoop.hbase.filter.Filter;
import org.apache.hadoop.hbase.filter.SubstringComparator;
import org.apache.hadoop.hbase.filter.ValueFilter;
import org.apache.hadoop.hbase.filter.WritableByteArrayComparable;
import org.apache.hadoop.hbase.util.Bytes;
public class TestHbaseDependentColumnFilter {
 String tableName = "test_value_filter";
 Configuration config = HBaseConfiguration.create();
 public void filter(boolean drop, CompareFilter.CompareOp operator,
 WritableByteArrayComparable comparator) throws IOException {
 HTable table = new HTable(config, tableName);
 //
 Filter filter;
 if (comparator != null) {
 // drop为true时，filter表示对"col1"列以外的所有"data1"列族数据做filter操作
 // drop为false时,表示对所有"data1"列族的数据做filter操作
 filter = new DependentColumnFilter(Bytes.toBytes("data1"),
 Bytes.toBytes("col1"), drop, operator, comparator);
 } else {
 filter = new DependentColumnFilter(Bytes.toBytes("data1"),
 Bytes.toBytes("col1"), drop);
 }
 // filter应用于scan
 Scan scan = new Scan();
 scan.setFilter(filter);
 ResultScanner scanner = table.getScanner(scan);
 for (Result result : scanner) {
 for (KeyValue kv : result.list()) {
 System.out.println("kv=" + kv.toString() + ",value="
 + Bytes.toString(kv.getValue()));
 }
 }
 scanner.close();
 table.close();
 }
 /**
 * 部分代码来自hbase权威指南
 * 
 * @throws IOException
 */
 public void testFilter() throws IOException {
 // The dropDependentColumn parameter is giving you additional control
 // over how the reference column is handled: it is either included or
 // dropped by the filter
 // 1.获取整个"data1"列族当前Version中的所有timestamp等于参照列"data1:col1"的数据
 System.out.println("drop=false");
 filter(false, CompareFilter.CompareOp.NO_OP, null);
 // 2.获取除了"col1"列以外的"data1"列族中的所有timestamp等于参照列"data1:col1"的数据
 System.out.println("drop=true");
 filter(true, CompareFilter.CompareOp.NO_OP, null);
 // 3.获取除了"col1"列以外的"data1"列族当前Version中的所有timestamp等于参照列"data1:col1"的,value以"data100"开头的所有数据
 System.out.println("比较");
 filter(true, CompareFilter.CompareOp.EQUAL, new BinaryPrefixComparator(
 Bytes.toBytes("data100")));
 }
 /**
 * 初始化数据
 */
 public void init() {
 // 创建表和初始化数据
 try {
 HBaseAdmin admin = new HBaseAdmin(config);
 if (!admin.tableExists(tableName)) {
 HTableDescriptor htd = new HTableDescriptor(tableName);
 HColumnDescriptor hcd1 = new HColumnDescriptor("data1");
 htd.addFamily(hcd1);
 HColumnDescriptor hcd2 = new HColumnDescriptor("data2");
 htd.addFamily(hcd2);
 HColumnDescriptor hcd3 = new HColumnDescriptor("data3");
 htd.addFamily(hcd3);
 admin.createTable(htd);
 }
 HTable table = new HTable(config, tableName);
 table.setAutoFlush(false);
 int count = 50;
 for (int i = 1; i <= count; ++i) {
 Put p = new Put(String.format("row%03d", i).getBytes());
 p.add("data1".getBytes(), String.format("col%01d", i % 10)
 .getBytes(), String.format("data1%03d", i).getBytes());
 p.add("data2".getBytes(), String.format("col%01d", i % 10)
 .getBytes(), String.format("data2%03d", i).getBytes());
 p.add("data3".getBytes(), String.format("col%01d", i % 10)
 .getBytes(), String.format("data3%03d", i).getBytes());
 table.put(p);
 }
 table.close();
 } catch (IOException e) {
 e.printStackTrace();
 }
 }
 /**
 * @param args
 * @throws IOException
 */
 public static void main(String[] args) throws IOException {
 TestHbaseDependentColumnFilter test = new TestHbaseDependentColumnFilter();
 test.init();
 test.testFilter();
 }
}

原文地址：Hbase DependentColumnFilter, 感谢原作者分享。