HBase Java客户端编程

本文以Hbase-0.92.0为例，介绍如何在Windows系统，Eclipse IDE集成环境下，使用Java语言，进行HBase客户端编程，包含建立表、删除表、插入记录、删除记录、各种方式下的查询操作等。

1. 准备工作

1、下载后安装jdk包;

2、下载eclipse，解压到本地;

3、下载HBase包，解压安装包到本地（这里使用的是 Hbase-0.92.0）。

2. 搭建开发环境

1、运行Eclipse，创建一个新的Java工程“HBaseClient”，右键项目根目录，选择 “Properties”->“Java Build Path”->“Library”->“Add External JARs”，将HBase解压后根目录下的hbase-0.92.0.jar、hbase-0.92.0-tests.jar和lib子目录下所有jar 包添加到本工程的Classpath下。

2、按照步骤1中的操作，将自己所连接的HBase的配置文件hbase-site.xml添加到本工程的Classpath中，如下所示为配置文件的一个示例：

<configuration>
<property>
<name>hbase.rootdir</name>
<value>hdfs://hadoop-1:9000/hbase</value>
</property>
<property>
<name>hbase.cluster.distributed</name>
<value>true</value>
</property>
<property>
<name>hbase.zookeeper.quorum</name>
<value>hadoop-1,hadoop-2,hadoop-3,hadoop-4</value>
</property>
<property>
<name>zookeeper.session.timeout</name>
<value>60000</value>
</property>
<property>
<name>hbase.master</name>
<value>hadoop-1:60000</value>
</property>
<property>
<name>hbase.zookeeper.property.clientPort</name>
<value>21818</value>
</property>
</configuration>

 3、下面可以在Eclipse环境下进行HBase编程了。

 

3. HBase基本操作代码示例

import java.io.IOException;   
import java.util.ArrayList;   
import java.util.List;   
    
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.KeyValue;   
import org.apache.hadoop.hbase.MasterNotRunningException;   
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.Result;   
import org.apache.hadoop.hbase.client.ResultScanner;   
import org.apache.hadoop.hbase.client.Scan;   
import org.apache.hadoop.hbase.client.Put;   
import org.apache.hadoop.hbase.util.Bytes;   
    
public class HBaseTest {     
       
    private static Configuration conf =null;
	 /**
	  * 初始化配置
	 */
	 static {
	     conf = HBaseConfiguration.create();
	 }
	 
    /**  
     * 创建一张表  
     */  
    public static void creatTable(String tableName, String[] familys) throws Exception {   
        HBaseAdmin admin = new HBaseAdmin(conf);   
        if (admin.tableExists(tableName)) {   
            System.out.println("table already exists!");   
        } else {   
            HTableDescriptor tableDesc = new HTableDescriptor(tableName);   
            for(int i=0; i<familys.length; i++){   
                tableDesc.addFamily(new HColumnDescriptor(familys[i]));   
            }   
            admin.createTable(tableDesc);   
            System.out.println("create table " + tableName + " ok.");   
        }    
    }   
       
    /**  
     * 删除表  
     */  
    public static void deleteTable(String tableName) throws Exception {   
       try {   
           HBaseAdmin admin = new HBaseAdmin(conf);   
           admin.disableTable(tableName);   
           admin.deleteTable(tableName);   
           System.out.println("delete table " + tableName + " ok.");   
       } catch (MasterNotRunningException e) {   
           e.printStackTrace();   
       } catch (ZooKeeperConnectionException e) {   
           e.printStackTrace();   
       }   
    }   
        
    /**  
     * 插入一行记录  
     */  
    public static void addRecord (String tableName, String rowKey, String family, String qualifier, String value)   
            throws Exception{   
        try {   
            HTable table = new HTable(conf, tableName);   
            Put put = new Put(Bytes.toBytes(rowKey));   
            put.add(Bytes.toBytes(family),Bytes.toBytes(qualifier),Bytes.toBytes(value));   
            table.put(put);   
            System.out.println("insert recored " + rowKey + " to table " + tableName +" ok.");   
        } catch (IOException e) {   
            e.printStackTrace();   
        }   
    }   
    
    /**  
     * 删除一行记录  
     */  
    public static void delRecord (String tableName, String rowKey) throws IOException{   
        HTable table = new HTable(conf, tableName);   
        List list = new ArrayList();   
        Delete del = new Delete(rowKey.getBytes());   
        list.add(del);   
        table.delete(list);   
        System.out.println("del recored " + rowKey + " ok.");   
    }   
        
    /**  
     * 查找一行记录  
     */  
    public static void getOneRecord (String tableName, String rowKey) throws IOException{   
        HTable table = new HTable(conf, tableName);   
        Get get = new Get(rowKey.getBytes());   
        Result rs = table.get(get);   
        for(KeyValue kv : rs.raw()){   
            System.out.print(new String(kv.getRow()) + " " );   
            System.out.print(new String(kv.getFamily()) + ":" );   
            System.out.print(new String(kv.getQualifier()) + " " );   
            System.out.print(kv.getTimestamp() + " " );   
            System.out.println(new String(kv.getValue()));   
        }   
    }   
        
    /**  
     * 显示所有数据  
     */  
    public static void getAllRecord (String tableName) {   
        try{   
             HTable table = new HTable(conf, tableName);   
             Scan s = new Scan();   
             ResultScanner ss = table.getScanner(s);   
             for(Result r:ss){   
                 for(KeyValue kv : r.raw()){   
                    System.out.print(new String(kv.getRow()) + " ");   
                    System.out.print(new String(kv.getFamily()) + ":");   
                    System.out.print(new String(kv.getQualifier()) + " ");   
                    System.out.print(kv.getTimestamp() + " ");   
                    System.out.println(new String(kv.getValue()));   
                 }   
             }   
        } catch (IOException e){   
            e.printStackTrace();   
        }   
    }   
       
    public static void  main (String [] agrs) {   
        try {   
            String tablename = "scores";   
            String[] familys = {"grade", "course"};   
            HBaseTest.creatTable(tablename, familys);   
                
            //add record zkb   
            HBaseTest.addRecord(tablename,"zkb","grade","","5");   
            HBaseTest.addRecord(tablename,"zkb","course","","90");   
            HBaseTest.addRecord(tablename,"zkb","course","math","97");   
            HBaseTest.addRecord(tablename,"zkb","course","art","87");   
            //add record  baoniu   
            HBaseTest.addRecord(tablename,"baoniu","grade","","4");   
            HBaseTest.addRecord(tablename,"baoniu","course","math","89");   
                
            System.out.println("===========get one record========");   
            HBaseTest.getOneRecord(tablename, "zkb");   
                
            System.out.println("===========show all record========");   
            HBaseTest.getAllRecord(tablename);   
                
            System.out.println("===========del one record========");   
            HBaseTest.delRecord(tablename, "baoniu");   
            HBaseTest.getAllRecord(tablename);   
                
            System.out.println("===========show all record========");   
            HBaseTest.getAllRecord(tablename);   
        } catch (Exception e) {   
            e.printStackTrace();   
        }   
    }   
}