亚洲无码一区在线播放 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();      
        }      
    }      
}   

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