Hbase之遍历获取数据

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转载：[Hbase之遍历获取数据] http://www.cnblogs.com/similarface/p/5799460.html

import org.apache.hadoop.conf.Configuration;import org.apache.hadoop.hbase.HBaseConfiguration;import org.apache.hadoop.hbase.TableName;import org.apache.hadoop.hbase.client.*;import org.apache.hadoop.hbase.util.Bytes;import java.io.IOException;/** * 遍历获取数据 */public class ScanAccessData {    public static void main(String[] args) throws IOException {        Configuration configuration = HBaseConfiguration.create();        Connection connection = ConnectionFactory.createConnection(configuration);        //建立表的连接        Table table = connection.getTable(TableName.valueOf("testtable"));        //创建一个空的Scan实例        Scan scan1 = new Scan();        //在行上获取遍历器        ResultScanner scanner1 = table.getScanner(scan1);        //打印行的值        for (Result res : scanner1) {            System.out.println(res);        }        //关闭释放资源        scanner1.close();        Scan scan2 = new Scan();        //添加限定列族        scan2.addFamily(Bytes.toBytes("colfam1"));        ResultScanner scanner2 = table.getScanner(scan2);        for (Result res : scanner2) {            System.out.println(res);        }        scanner2.close();        Scan scan3 = new Scan();        //添加限定列族 列分隔 行偏移        scan3.addColumn(Bytes.toBytes("colfam1"), Bytes.toBytes("col-5")).                addColumn(Bytes.toBytes("colfam2"), Bytes.toBytes("col-33")).                setStartRow(Bytes.toBytes("row-10")).                setStopRow(Bytes.toBytes("row-20"));        ResultScanner scanner3 = table.getScanner(scan3);        for (Result res : scanner3) {            System.out.println(res);        }        scanner3.close();        Scan scan4 = new Scan();        scan4.addColumn(Bytes.toBytes("colfam1"),                Bytes.toBytes("col-5")).                setStartRow(Bytes.toBytes("row-10")).                setStopRow(Bytes.toBytes("row-20"));        ResultScanner scanner4 = table.getScanner(scan4);        for (Result res : scanner4) {            System.out.println(res);        }        scanner4.close();        Scan scan5 = new Scan();        //添加倒序        scan5.addColumn(Bytes.toBytes("colfam1"), Bytes.toBytes("col-5")).                setStartRow(Bytes.toBytes("row-20")).                setStopRow(Bytes.toBytes("row-10")).                setReversed(true);        ResultScanner scanner5 = table.getScanner(scan5);        for (Result res : scanner5) {            System.out.println(res);        }        scanner5.close();    }}
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