头哥实践平台----HBase 开发：使用Java操作HBase 头哥实践平台----HBase 开发：使用Java操作HBase

一.第1关：创建表

1.先写命令行

start-dfs.sh
start-hbase.sh
hadoop fs -ls /hbase(可有可无)

2.再写代码文件

package step1;
import java.io.IOException;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.HBaseConfiguration;
import org.apache.hadoop.hbase.HColumnDescriptor;
import org.apache.hadoop.hbase.HTableDescriptor;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.client.Admin;
import org.apache.hadoop.hbase.client.ColumnFamilyDescriptor;
import org.apache.hadoop.hbase.client.ColumnFamilyDescriptorBuilder;
import org.apache.hadoop.hbase.client.Connection;
import org.apache.hadoop.hbase.client.ConnectionFactory;
import org.apache.hadoop.hbase.client.Get;
import org.apache.hadoop.hbase.client.Put;
import org.apache.hadoop.hbase.client.Result;
import org.apache.hadoop.hbase.client.ResultScanner;
import org.apache.hadoop.hbase.client.Scan;
import org.apache.hadoop.hbase.client.Table;
import org.apache.hadoop.hbase.client.TableDescriptor;
import org.apache.hadoop.hbase.client.TableDescriptorBuilder;
import org.apache.hadoop.hbase.util.Bytes;
public class Task{
	public void createTable()throws Exception{
	/********* Begin *********/
	Configuration config = HBaseConfiguration.create();
	Connection connection = ConnectionFactory.createConnection(config);
	try {
	// Create table
	Admin admin = connection.getAdmin();
	try {
	TableName tableName = TableName.valueOf("dept");
	// 新 API 构建表
	// TableDescriptor 对象通过 TableDescriptorBuilder 构建；
	TableDescriptorBuilder tableDescriptor =
	TableDescriptorBuilder.newBuilder(tableName);
	ColumnFamilyDescriptor family = ColumnFamilyDescriptorBuilder.newBuilder(Bytes.toBytes("data")).build();// 构建列族对象
	tableDescriptor.setColumnFamily(family); // 设置列族
	admin.createTable(tableDescriptor.build()); // 创建表
	TableName emp = TableName.valueOf("emp");
	// 新 API 构建表
	// TableDescriptor 对象通过 TableDescriptorBuilder 构建；
	TableDescriptorBuilder empDescriptor =
	TableDescriptorBuilder.newBuilder(emp);
	ColumnFamilyDescriptor empfamily =
	ColumnFamilyDescriptorBuilder.newBuilder(Bytes.toBytes("emp")).build();// 构建列族对象
	empDescriptor.setColumnFamily(empfamily); // 设置列族
	admin.createTable(empDescriptor.build()); // 创建表
	} finally {
	admin.close();
	}
	} finally {
	connection.close();
	}
	/********* End *********/
	}
}

3.运行

二.第2关：添加数据

1.先写命令行

start-dfs.sh
start-hbase.sh

2.再写代码文件

package step2;
import java.io.IOException;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.HBaseConfiguration;
import org.apache.hadoop.hbase.HColumnDescriptor;
import org.apache.hadoop.hbase.HTableDescriptor;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.client.Admin;
import org.apache.hadoop.hbase.client.ColumnFamilyDescriptor;
import org.apache.hadoop.hbase.client.ColumnFamilyDescriptorBuilder;
import org.apache.hadoop.hbase.client.Connection;
import org.apache.hadoop.hbase.client.ConnectionFactory;
import org.apache.hadoop.hbase.client.Get;
import org.apache.hadoop.hbase.client.Put;
import org.apache.hadoop.hbase.client.Result;
import org.apache.hadoop.hbase.client.ResultScanner;
import org.apache.hadoop.hbase.client.Scan;
import org.apache.hadoop.hbase.client.Table;
import org.apache.hadoop.hbase.client.TableDescriptor;
import org.apache.hadoop.hbase.client.TableDescriptorBuilder;
import org.apache.hadoop.hbase.util.Bytes;
public class Task {
	public void insertInfo()throws Exception{
	/********* Begin *********/
	Configuration config = HBaseConfiguration.create();
 	Connection connection = ConnectionFactory.createConnection(config);
 	Admin admin = connection.getAdmin();
 	TableName tableName = TableName.valueOf("tb_step2");
 	TableDescriptorBuilder tableDescriptor = TableDescriptorBuilder.newBuilder(tableName);
 	ColumnFamilyDescriptor family = ColumnFamilyDescriptorBuilder.newBuilder(Bytes.toBytes("data")).build();// 构建列族对象
 	tableDescriptor.setColumnFamily(family); // 设置列族
 	admin.createTable(tableDescriptor.build()); // 创建表
 	// 添加数据
 	byte[] row1 = Bytes.toBytes("row1");
 	Put put1 = new Put(row1); 
 	byte[] columnFamily1 = Bytes.toBytes("data"); // 列
 	byte[] qualifier1 = Bytes.toBytes(String.valueOf(1)); // 列族修饰词
	byte[] value1 = Bytes.toBytes("张三丰"); // 值
	put1.addColumn(columnFamily1, qualifier1, value1);
	byte[] row2 = Bytes.toBytes("row2");
	Put put2 = new Put(row2); 
	byte[] columnFamily2 = Bytes.toBytes("data"); // 列
	byte[] qualifier2 = Bytes.toBytes(String.valueOf(2)); // 列族修饰词
	byte[] value2 = Bytes.toBytes("张无忌"); // 值
	put2.addColumn(columnFamily2, qualifier2, value2);
	Table table = connection.getTable(tableName);
	table.put(put1);
	table.put(put2);
	/********* End *********/
	}
}

3.运行

三.第3关：获取数据

1.先写命令行

start-dfs.sh
start-hbase.sh

2.再写代码文件

package step3;
import java.io.IOException;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.HBaseConfiguration;
import org.apache.hadoop.hbase.HColumnDescriptor;
import org.apache.hadoop.hbase.HTableDescriptor;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.client.Admin;
import org.apache.hadoop.hbase.client.ColumnFamilyDescriptor;
import org.apache.hadoop.hbase.client.ColumnFamilyDescriptorBuilder;
import org.apache.hadoop.hbase.client.Connection;
import org.apache.hadoop.hbase.client.ConnectionFactory;
import org.apache.hadoop.hbase.client.Get;
import org.apache.hadoop.hbase.client.Put;
import org.apache.hadoop.hbase.client.Result;
import org.apache.hadoop.hbase.client.ResultScanner;
import org.apache.hadoop.hbase.client.Scan;
import org.apache.hadoop.hbase.client.Table;
import org.apache.hadoop.hbase.client.TableDescriptor;
import org.apache.hadoop.hbase.client.TableDescriptorBuilder;
import org.apache.hadoop.hbase.util.Bytes;
public class Task {
	public void queryTableInfo()throws Exception{
	/********* Begin *********/
	Configuration config = HBaseConfiguration.create();
	Connection connection = ConnectionFactory.createConnection(config);
 	Admin admin = connection.getAdmin();
 	TableName tableName = TableName.valueOf("t_step3");
 	Table table = connection.getTable(tableName);
 	// 获取数据
 	Get get = new Get(Bytes.toBytes("row1")); // 定义 get 对象
 	Result result = table.get(get); // 通过 table 对象获取数据
 	//System.out.println("Result: " + result);
	// 很多时候我们只需要获取“值” 这里表示获取 data:1 列族的值
	byte[] valueBytes = result.getValue(Bytes.toBytes("data"), Bytes.toBytes("1")); // 获取到的是字节数组
 	// 将字节转成字符串
	String valueStr = new String(valueBytes,"utf-8");
	System.out.println("value:" + valueStr);
	TableName tableStep3Name = TableName.valueOf("table_step3");
	Table step3Table = connection.getTable(tableStep3Name);
	// 批量查询
	Scan scan = new Scan();
	ResultScanner scanner = step3Table.getScanner(scan);
 	try {
	 int i = 0;
	 for (Result scannerResult: scanner) {
	 //byte[] value = scannerResult.getValue(Bytes.toBytes("data"), Bytes.toBytes(1));
	 // System.out.println("Scan: " + scannerResult);
	 byte[] row = scannerResult.getRow();
	 System.out.println("rowName:" + new String(row,"utf-8"));
	 }
 	} finally {
 	scanner.close();
 	}
	
	
	
	
	/********* End *********/
	}
	
}

3.运行

四.第4关：删除表

1.先写命令行

start-dfs.sh
start-hbase.sh

2.再写代码文件

package step4;
import java.io.IOException;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.HBaseConfiguration;
import org.apache.hadoop.hbase.HColumnDescriptor;
import org.apache.hadoop.hbase.HTableDescriptor;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.client.Admin;
import org.apache.hadoop.hbase.client.ColumnFamilyDescriptor;
import org.apache.hadoop.hbase.client.ColumnFamilyDescriptorBuilder;
import org.apache.hadoop.hbase.client.Connection;
import org.apache.hadoop.hbase.client.ConnectionFactory;
import org.apache.hadoop.hbase.client.Get;
import org.apache.hadoop.hbase.client.Put;
import org.apache.hadoop.hbase.client.Result;
import org.apache.hadoop.hbase.client.ResultScanner;
import org.apache.hadoop.hbase.client.Scan;
import org.apache.hadoop.hbase.client.Table;
import org.apache.hadoop.hbase.client.TableDescriptor;
import org.apache.hadoop.hbase.client.TableDescriptorBuilder;
import org.apache.hadoop.hbase.util.Bytes;
public class Task {
	
	
	public void deleteTable()throws Exception{
	/********* Begin *********/
	Configuration config = HBaseConfiguration.create();
	Connection connection = ConnectionFactory.createConnection(config);
	Admin admin = connection.getAdmin();
	TableName tableName = TableName.valueOf("t_step4");
	admin.disableTable(tableName);	
	admin.deleteTable(tableName);
	
	/********* End *********/
	}
}

3.运行