实验:熟悉常用的HBase操作

 create 's1','score'

put 's1','zhangsan','score:Math','69'

delete 's1','zhangsan','score:Math'

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.*;
import org.apache.hadoop.hbase.client.*;
import org.apache.hadoop.hbase.util.Bytes;
import java.io.IOException;
public class test3{
    public static Configuration configuration;
    public static Connection connection;
    public static Admin admin;
    public static void init(){
        configuration = HBaseConfiguration.create();
        configuration.set("Hbase.rootdir","hdfs://localhost:9000/hbase");
        try{
            connection = ConnectionFactory.createConnection(configuration);
            admin = connection.getAdmin();
        }catch (IOException e){
            e.printStackTrace();
        }
    }
    public static void close(){
        try {
            if(admin != null) {
                admin.close();
            }
        }catch (IOException e){
            e.printStackTrace();
        }
    }
    //向表添加数据
    public static void insterRow(String tableName, String RowKey, String columnFamily, String column, String value) throws IOException{
        init();
        Table table = connection.getTable(TableName.valueOf(tableName));
        Put put = new Put(RowKey.getBytes());
        put.addColumn(columnFamily.getBytes(),column.getBytes(),value.getBytes());
        table.put(put);
        table.close();
        close();
    }
    //删除数据
    public static void deleRow(String tableName, String RowKey, String columnFamily, String column) throws IOException{
        init();
        Table table = connection.getTable(TableName.valueOf(tableName));
        Delete delete = new Delete(Bytes.toBytes(RowKey));
        delete.addColumn(Bytes.toBytes(columnFamily), Bytes.toBytes(column));
        //删除指定的列族
        //delete.addFamily(Bytes.toBytes(columnFamily));
        table.delete(delete);
        table.close();
        close();
    }
    public static void main(String[] args)throws IOException{
        init();
        insterRow("s1","zhangsan","score","Math","69");//添加指定列
        deleRow("s1","zhangsan","score","Math");//删除指定列
        close();
    }
}

 （4）清空指定的表的所有记录数据；
清空custor表的所有记录数据

 truncate 's1'

 Java

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.*;
import org.apache.hadoop.hbase.client.*;
import java.io.IOException;
public class test4 {
    public static Configuration configuration;
    public static Connection connection;
    public static Admin admin;
    public static void init(){
        configuration = HBaseConfiguration.create();
        configuration.set("Hbase.rootdir","hdfs://localhost:9000/hbase");
        try{
            connection = ConnectionFactory.createConnection(configuration);
            admin = connection.getAdmin();
        }catch (IOException e){
            e.printStackTrace();
        }
    }
    public static void close(){
        try {
            if(admin != null) {
                admin.close();
            }
        }catch (IOException e){
            e.printStackTrace();
        }
    }

    //清空指定的表的所有记录数据
    public static void clearRows(String tableName) throws IOException{
        Table table = connection.getTable(TableName.valueOf(tableName));
        Scan scan = new Scan();
        scan.getAllowPartialResults();
        ResultScanner resultScanner = table.getScanner(scan);
        for(Result result:resultScanner){
            Cell[] cells = result.rawCells();
            for (Cell cell : cells) {
                Delete delete = new Delete(CellUtil.cloneRow(cell));
                table.delete(delete);
            }
        }
        System.out.println("删除完毕");
    }

    public static void main(String[] args)throws IOException{
        init();
        clearRows("s1");
        close();
    }
}

（5）统计表的行数。
统计Student表的行数：

count 's1'

 根据（3）再建回表s1,(可自行决定)

create 's1','score'
put 's1','zhangsan','score:Math','69'
delete 's1','zhangsan','score:Math'