Hbase遍历方式

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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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