大数据从入门到实战——HBase高级特性：过滤器（一）

• 使用过滤器查询指定行的数据
• 使用正则表达式与子字符串匹配行键
• 列族过滤器、值过滤器、列名过滤器

package step1;

import java.io.IOException;

import org.apache.hadoop.cli.util.*;
import org.apache.hadoop.conf.*;
import org.apache.hadoop.hbase.*;
import org.apache.hadoop.hbase.client.*;
import org.apache.hadoop.hbase.filter.*;
import org.apache.hadoop.hbase.util.*;

public class Task {

	public void query(String tName) throws Exception {
		
		Configuration config = new Configuration();
		Connection conn = ConnectionFactory.createConnection(config);

		TableName tableName = TableName.valueOf(tName);
 		Table table = conn.getTable(tableName);
 		Scan scan1 = new Scan();
 		scan1.addColumn(Bytes.toBytes("basic_info"), Bytes.toBytes("gender"));
 		Filter filter1 = new RowFilter(CompareOperator.EQUAL,
 		new BinaryComparator(Bytes.toBytes("2018")));
 		scan1.setFilter(filter1);
 		ResultScanner scanner1 = table.getScanner(scan1);
 		System.out.println("row:2018");
 		for (Result result : scanner1) {
 			for(Cell cell : result.listCells()){
 				System.out.println("basic_info:gender " + new String(CellUtil.clonevalue(cell),"utf-8") );
 			}
 		}
 		scanner1.close();
 		Scan scan2 = new Scan();
 		scan2.addColumn(Bytes.toBytes("school_info"), Bytes.toBytes("college"));
 		Filter filter2 = new RowFilter(CompareOperator.GREATER,
 		new BinaryComparator(Bytes.toBytes("2018")));
 		scan2.setFilter(filter2);
 		ResultScanner scanner2 = table.getScanner(scan2);
 		for (Result result : scanner2) {
 			System.out.println("row:" + new String(result.getRow(),"utf-8"));
 			for(Cell cell : result.listCells()){
 				System.out.println("school_info:college " + new String(CellUtil.clonevalue(cell),"utf-8") );
 			}
 		}
 		scanner2.close();
 		Scan scan3 = new Scan();
 		scan3.addColumn(Bytes.toBytes("basic_info"), Bytes.toBytes("name"));
 		Filter filter3 = new RowFilter(CompareOperator.LESS_OR_EQUAL,
 		new BinaryComparator(Bytes.toBytes("2020")));
 		scan3.setFilter(filter3);
 		ResultScanner scanner3 = table.getScanner(scan3);
 		for (Result result : scanner3) {
 			System.out.println("row:" + new String(result.getRow(),"utf-8"));
 			for(Cell cell : result.listCells()){
 				System.out.println("basic_info:name " + new String(CellUtil.clonevalue(cell),"utf-8") );
 			}
 		}
 		scanner3.close();
		
		conn.close();
		
	}
}

package step2;

import java.io.IOException;

import org.apache.hadoop.cli.util.*;
import org.apache.hadoop.conf.*;
import org.apache.hadoop.hbase.*;
import org.apache.hadoop.hbase.client.*;
import org.apache.hadoop.hbase.filter.*;
import org.apache.hadoop.hbase.util.*;
import org.apache.hadoop.hbase.filter.SubstringComparator;

public class Task {

	public void query() throws Exception {
		
		Configuration config = new Configuration();
		Connection conn = ConnectionFactory.createConnection(config);
		
		TableName tableName = TableName.valueOf("t2_student_table");
 		Table table = conn.getTable(tableName);
 		Scan scan1 = new Scan();
 		Filter filter1 = new RowFilter(CompareOperator.EQUAL,new RegexStringComparator("1.*9$")); //匹配任意开头，以2结尾。
 		scan1.setFilter(filter1);
 		ResultScanner scanner1 = table.getScanner(scan1);
 		for (Result result : scanner1) {
 			System.out.println("row:" + new String(result.getRow(),"utf-8"));
 			for(Cell cell : result.listCells()){
 				String family = Bytes.toString(CellUtil.cloneFamily(cell));
 				String qualifier = Bytes.toString(CellUtil.cloneQualifier(cell));
 				String value = Bytes.toString(CellUtil.clonevalue(cell));
 				System.out.println(family + ":" + qualifier + " " + value);
 			}
 		}
 		scanner1.close();
 		Scan scan2 = new Scan();
 		Filter filter2 = new RowFilter(CompareOperator.EQUAL,new SubstringComparator("231"));
 		scan2.setFilter(filter2);
 		ResultScanner scanner2 = table.getScanner(scan2);
 		for (Result result : scanner2) {
 			System.out.println("row:" + new String(result.getRow(),"utf-8"));
 			for(Cell cell : result.listCells()){
 				String family = Bytes.toString(CellUtil.cloneFamily(cell));
 				String qualifier = Bytes.toString(CellUtil.cloneQualifier(cell));
 				String value = Bytes.toString(CellUtil.clonevalue(cell));
 				System.out.println(family + ":" + qualifier + " " + value);
			}
 		}
 		scanner2.close();

		
		
		
		
		
		conn.close();
		
	}
}

package step3;

import java.io.IOException;

import org.apache.hadoop.cli.util.*;
import org.apache.hadoop.conf.*;
import org.apache.hadoop.hbase.*;
import org.apache.hadoop.hbase.client.*;
import org.apache.hadoop.hbase.filter.*;
import org.apache.hadoop.hbase.util.*;

import org.apache.hadoop.hbase.filter.SubstringComparator;

public class Task {

	public void query() throws Exception {
		
		Configuration config = new Configuration();
		Connection conn = ConnectionFactory.createConnection(config);
		
		TableName tableName = TableName.valueOf(Bytes.toBytes("t3_student_table"));
 		Table table = conn.getTable(tableName);
 		
		Filter filter1 = new FamilyFilter(CompareOperator.EQUAL,
 		new BinaryComparator(Bytes.toBytes("school_info")));
 		Get get1 = new Get(Bytes.toBytes("1019"));
 		get1.setFilter(filter1);
 		Result result1 = table.get(get1);
 		System.out.println("row:" + new String(result1.getRow(),"utf-8"));
 		for(Cell cell : result1.listCells()){
 			String family = Bytes.toString(CellUtil.cloneFamily(cell));
 			String qualifier = Bytes.toString(CellUtil.cloneQualifier(cell));
 			String value = Bytes.toString(CellUtil.clonevalue(cell));
 			System.out.println(family + ":" + qualifier + " " + value);
 		}
 
 		Filter filter2 = new QualifierFilter(CompareOperator.EQUAL,
 		new SubstringComparator("c"));
 		Get get2 = new Get(Bytes.toBytes("2020"));
 		get2.setFilter(filter2);
 		Result result2 = table.get(get2);
 		System.out.println("row:" + new String(result2.getRow(),"utf-8"));
 		for(Cell cell : result2.listCells()){
 			String family = Bytes.toString(CellUtil.cloneFamily(cell));
 			String qualifier = Bytes.toString(CellUtil.cloneQualifier(cell));
 			String value = Bytes.toString(CellUtil.clonevalue(cell));
 			System.out.println(family + ":" + qualifier + " " + value);
 		}
 
 		Scan scan3 = new Scan();
 		Filter filter3 = new ValueFilter(CompareOperator.EQUAL, new SubstringComparator("寮 "));
 		scan3.setFilter(filter3);
 		ResultScanner scanner3 = table.getScanner(scan3);
 		for (Result result : scanner3) {
 			System.out.println("row:" + new String(result.getRow(),"utf-8"));
 			for(Cell cell : result.listCells()){
 				String family = Bytes.toString(CellUtil.cloneFamily(cell));
 				String qualifier = Bytes.toString(CellUtil.cloneQualifier(cell));
 				String value = Bytes.toString(CellUtil.clonevalue(cell));
 				System.out.println(family + ":" + qualifier + " " + value);
 			}
 		}
 		scanner3.close();

		
		
		
		
		
		conn.close();
		
	}
}