HBase编程 API入门系列之modify(管理端而言)(10)

时间:2021-10-19 05:18:47

  这里,我带领大家,学习更高级的,因为,在开发中,尽量不能去服务器上修改表。

  所以,在管理端来修改HBase表。采用线程池的方式(也是生产开发里首推的)

package zhouls.bigdata.HbaseProject.Pool;

import java.io.IOException;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.HBaseConfiguration;
import org.apache.hadoop.hbase.client.HConnection;
import org.apache.hadoop.hbase.client.HConnectionManager;


public class TableConnection {
private TableConnection(){
}
private static HConnection connection = null;
public static HConnection getConnection(){
if(connection == null){
ExecutorService pool = Executors.newFixedThreadPool(10);//建立一个固定大小的线程池
Configuration conf = HBaseConfiguration.create();
conf.set("hbase.zookeeper.quorum","HadoopMaster:2181,HadoopSlave1:2181,HadoopSlave2:2181");
try{
connection = HConnectionManager.createConnection(conf,pool);//创建连接时,拿到配置文件和线程池
}catch (IOException e){
}
}
return connection;
}
}

1、修改HBase表

暂时,有错误

package zhouls.bigdata.HbaseProject.Pool;

import java.io.IOException;

import zhouls.bigdata.HbaseProject.Pool.TableConnection;

import javax.xml.transform.Result;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.Cell;
import org.apache.hadoop.hbase.CellUtil;
import org.apache.hadoop.hbase.HBaseConfiguration;
import org.apache.hadoop.hbase.HColumnDescriptor;
import org.apache.hadoop.hbase.HTableDescriptor;
import org.apache.hadoop.hbase.MasterNotRunningException;
import org.apache.hadoop.hbase.NamespaceDescriptor;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.ZooKeeperConnectionException;
import org.apache.hadoop.hbase.client.Delete;
import org.apache.hadoop.hbase.client.Get;
import org.apache.hadoop.hbase.client.HBaseAdmin;
import org.apache.hadoop.hbase.client.HTable;
import org.apache.hadoop.hbase.client.HTableInterface;
import org.apache.hadoop.hbase.client.Put;
import org.apache.hadoop.hbase.client.ResultScanner;
import org.apache.hadoop.hbase.client.Scan;
import org.apache.hadoop.hbase.util.Bytes;

public class HBaseTest {

public static void main(String[] args) throws Exception {
// HTable table = new HTable(getConfig(),TableName.valueOf("test_table"));//表名是test_table
// Put put = new Put(Bytes.toBytes("row_04"));//行键是row_04
// put.add(Bytes.toBytes("f"),Bytes.toBytes("name"),Bytes.toBytes("Andy1"));//列簇是f,列修饰符是name,值是Andy0
// put.add(Bytes.toBytes("f2"),Bytes.toBytes("name"),Bytes.toBytes("Andy3"));//列簇是f2,列修饰符是name,值是Andy3
// table.put(put);
// table.close();

// Get get = new Get(Bytes.toBytes("row_04"));
// get.addColumn(Bytes.toBytes("f1"), Bytes.toBytes("age"));如现在这样,不指定,默认把所有的全拿出来
// org.apache.hadoop.hbase.client.Result rest = table.get(get);
// System.out.println(rest.toString());
// table.close();

// Delete delete = new Delete(Bytes.toBytes("row_2"));
// delete.deleteColumn(Bytes.toBytes("f1"), Bytes.toBytes("email"));
// delete.deleteColumn(Bytes.toBytes("f1"), Bytes.toBytes("name"));
// table.delete(delete);
// table.close();


// Delete delete = new Delete(Bytes.toBytes("row_04"));
//// delete.deleteColumn(Bytes.toBytes("f"), Bytes.toBytes("name"));//deleteColumn是删除某一个列簇里的最新时间戳版本。
// delete.deleteColumns(Bytes.toBytes("f"), Bytes.toBytes("name"));//delete.deleteColumns是删除某个列簇里的所有时间戳版本。
// table.delete(delete);
// table.close();


// Scan scan = new Scan();
// scan.setStartRow(Bytes.toBytes("row_01"));//包含开始行键
// scan.setStopRow(Bytes.toBytes("row_03"));//不包含结束行键
// scan.addColumn(Bytes.toBytes("f"), Bytes.toBytes("name"));
// ResultScanner rst = table.getScanner(scan);//整个循环
// System.out.println(rst.toString());
// for (org.apache.hadoop.hbase.client.Result next = rst.next();next !=null;next = rst.next() )
// {
// for(Cell cell:next.rawCells()){//某个row key下的循坏
// System.out.println(next.toString());
// System.out.println("family:" + Bytes.toString(CellUtil.cloneFamily(cell)));
// System.out.println("col:" + Bytes.toString(CellUtil.cloneQualifier(cell)));
// System.out.println("value" + Bytes.toString(CellUtil.cloneValue(cell)));
// }
// }
// table.close();

HBaseTest hbasetest =new HBaseTest();
// hbasetest.insertValue();
// hbasetest.getValue();
// hbasetest.delete();
// hbasetest.scanValue();
hbasetest.createTable("test_table3", "f");//先判断表是否存在,再来创建HBase表(生产开发首推)
// hbasetest.deleteTable("test_table4");//先判断表是否存在,再来删除HBase表(生产开发首推)
// hbasetest.modifyTable("test_table","row_02","f",‘f:age‘);
}


//生产开发中,建议这样用线程池做
// public void insertValue() throws Exception{
// HTableInterface table = TableConnection.getConnection().getTable(TableName.valueOf("test_table"));
// Put put = new Put(Bytes.toBytes("row_01"));//行键是row_01
// put.add(Bytes.toBytes("f"),Bytes.toBytes("name"),Bytes.toBytes("Andy0"));
// table.put(put);
// table.close();
// }