目錄

一：跳轉過濾器（SkipFilter）

跳轉過濾器包裝了一個使用者提供的過濾器，當被包裝的過濾器遇到一個需要過濾的KeyValue例項時，使用者可以拓展並過濾到整行資料。換言之，當過濾器發現某一行中的一列被過濾時，那麼整行都會被過濾掉。案例將SkipFilter和ValueFilter組合起來獲取不包含空列值的行，同時過濾掉不符合條件的的行。

package appendFilter;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.HBaseConfiguration;
import org.apache.hadoop.hbase.KeyValue;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.client.*;
import org.apache.hadoop.hbase.filter.*;
import org.apache.hadoop.hbase.util.Bytes;
import org.junit.Test;

import java.io.IOException;

public class skipFilter {

    private Configuration configuration = null;
    private Connection connection = null;
    @Test
    public void skipFilter() throws IOException {
        System.out.println("begin");
        configuration = HBaseConfiguration.create();
        connection = ConnectionFactory.createConnection(configuration);
        Table table = connection.getTable(TableName.valueOf("ns1:t1"));
        Filter filter = new ValueFilter(CompareFilter.CompareOp.NOT_EQUAL,new BinaryComparator(Bytes.toBytes("ccc")));
        Scan scan = new Scan();
        scan.setFilter(filter);
        ResultScanner resultScanner = table.getScanner(scan);
        for(Result result:resultScanner){
            for (KeyValue kv : result.raw()) {
                System.out.println("KV: "+kv+",value: "+Bytes.toString(kv.getValue()));
            }
        }
        resultScanner.close();

        System.out.println("-------------------------------------------------");
        Filter filter1 = new SkipFilter(filter);
        Scan scan1 = new Scan();
        scan1.setFilter(filter1);
        ResultScanner resultScanner1 = table.getScanner(scan1);
        for(Result result1:resultScanner1){
            for (KeyValue kv : result1.raw()) {
                System.out.println("KV: "+kv+",value: "+Bytes.toString(kv.getValue()));
            }
        }
        resultScanner1.close();
        table.close();
        System.out.println("end");
    }
}
 

結果顯示：

二：全匹配過濾器（WhileMatchFilter）

全匹配過濾器和跳轉過濾器相似，不過當一條資料被過濾掉時，它就會直接放棄這次掃描操作

package appendFilter;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.HBaseConfiguration;
import org.apache.hadoop.hbase.KeyValue;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.client.*;
import org.apache.hadoop.hbase.filter.*;
import org.apache.hadoop.hbase.util.Bytes;
import org.junit.Test;

import java.io.IOException;

public class whileMatchFilter {
    private Configuration configuration = null;
    private Connection connection = null;
    @Test
    public void whileMatchFilter() throws IOException {
        System.out.println("begin");
        configuration = HBaseConfiguration.create();
        connection = ConnectionFactory.createConnection(configuration);
        Table table = connection.getTable(TableName.valueOf("ns1:t1"));
        Filter filter = new RowFilter(CompareFilter.CompareOp.NOT_EQUAL,new BinaryComparator(Bytes.toBytes("row3")));
        Scan scan = new Scan();
        scan.setFilter(filter);
        ResultScanner resultScanner = table.getScanner(scan);
        for(Result result:resultScanner){
            for (KeyValue kv : result.raw()) {
                System.out.println("KV: "+kv+",value: "+Bytes.toString(kv.getValue()));
            }
        }
        resultScanner.close();

        System.out.println("-------------------------------------------------");
        Filter filter1 = new WhileMatchFilter(filter);
        Scan scan1 = new Scan();
        scan1.setFilter(filter1);
        ResultScanner resultScanner1 = table.getScanner(scan1);
        for(Result result1:resultScanner1){
            for (KeyValue kv : result1.raw()) {
                System.out.println("KV: "+kv+",value: "+Bytes.toString(kv.getValue()));
            }
        }
        resultScanner1.close();
        table.close();
        System.out.println("end");
    }
}
 

結果展示：