使用Hive编写Mapreduce代码

首先需要打开hive服务

bin/hive –service hiveserver

完整代码

package com.hive.demo;

import java.util.List;  
import org.apache.hadoop.hive.service.ThriftHive;  
import org.apache.hadoop.hive.service.ThriftHive.Client;  
import org.apache.thrift.TException;  
import org.apache.thrift.protocol.TBinaryProtocol;  
import org.apache.hadoop.hive.service.HiveServerException;  
import org.apache.thrift.transport.TSocket; 

public class Hive_demo_01 {
	/**
	 * @param args
	 */
	static TSocket transport;

	private static Client getClient(String hiveServer, Integer hivePort) {
		final int SOME_BIG_NUMBER = 99999999;
		Client client = null;
		try {
			transport = new TSocket(hiveServer, hivePort);
			transport.setTimeout(SOME_BIG_NUMBER);
			transport.open();
			TBinaryProtocol protocol = new TBinaryProtocol(transport);
			client = new ThriftHive.Client(protocol);
			System.out.println("Connection is established");
			return client;
		} catch (Exception e) {
			e.printStackTrace();
			return null;
		}
	}

	private Client create_dbs(Client c1,String db_name) {  
        try {  
            c1.execute("create database "+db_name);  
        } catch (HiveServerException e) {  
            // TODO Auto-generated catch block  
            e.printStackTrace();  
        } catch (TException e) {  
            // TODO Auto-generated catch block  
            e.printStackTrace();  
        }  
        System.out.println(" *** create jdbc_demo database *** ");  
        System.out.println(" -------------------------------- ");  
        return c1;  
    }  
	private Client useDB(Client c1,String db_name) {  
        try {  
            c1.execute("use "+db_name);  
        } catch (HiveServerException e) {  
            // TODO Auto-generated catch block  
            e.printStackTrace();  
        } catch (TException e) {  
            // TODO Auto-generated catch block  
            e.printStackTrace();  
        }  
        System.out.println(" *** change database *** ");  
        System.out.println(" -------------------------------- ");  
        return c1;  
    }  
	
	private Client create_tables(Client c1) {  
        try {  
            c1.execute("create table sample_data(name string)stored as textfile");  
        } catch (HiveServerException e) {  
            // TODO Auto-generated catch block  
            e.printStackTrace();  
        } catch (TException e) {  
            // TODO Auto-generated catch block  
            e.printStackTrace();  
        }  
        System.out.println(" *** sample_data tables is created *** ");  
        System.out.println(" -------------------------------- ");  
        Client c2 = c1;  
        return c2;  
    }  
	
	private Client show_tables(Client c1) {  
        try {  
            try {  
                c1.execute("show tables");  
            } catch (TException e) {  
                // TODO Auto-generated catch block  
                e.printStackTrace();  
            }  
            List li = null;  
            try {  
                li = c1.fetchAll();  
            } catch (TException e) {  
                // TODO Auto-generated catch block  
                e.printStackTrace();  
            }  
            System.out.println(" *** The Tables List *** ");  
            for (String string : li) {  
                System.out.println(string);  
            }  
            System.out.println(" -------------------------------- ");  
            Client c2 = c1;  
            return c2;  
        } finally {  
        }  
    }  
  
    
  
    private Client load_data(Client c1, String tbl_name) {  
        try {  
            c1.execute("load data local inpath '/home/wcbdd/Desktop/week5/sample.txt' into table "+tbl_name);  
        } catch (HiveServerException e) {  
            // TODO Auto-generated catch block  
            e.printStackTrace();  
        } catch (TException e) {  
            // TODO Auto-generated catch block  
            e.printStackTrace();  
        }  
        System.out.println(" *** loaded data into " + tbl_name + " *** ");  
        System.out.println(" -------------------------------- ");  
        Client c2 = c1;  
        return c2;  
    }  
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		String HIVE_SERVER = "localhost";
		Integer HIVE_PORT = new Integer(10000);
		Client client = getClient(HIVE_SERVER, HIVE_PORT);
        Hive_demo_01 obj = new Hive_demo_01(); 
        String db_name="jdbc_demo";
        System.out.println(" create database");
        client = obj.create_dbs(client,db_name); 
        client = obj.useDB(client,db_name); 
        client = obj.show_tables(client);  
        System.out.println(" Before Creating the table sample_data ");  
        client = obj.create_tables(client);  
        System.out.println(" After Creating the table sample_data ");  
        client = obj.show_tables(client);  
        System.out.println(" loading data into sample_data ");  
        client = obj.load_data(client, "sample_data"); 
		transport.close();
	}
}