Java 调用Hive 自定义UDF

Hive 具有一个可选的组件叫做HiveServer,它允许通过在一定的端口访问Hive.

将自定义的UDF的jar拷贝到安装的hive服务器中（如 /home/hadoop下）

具体的不啰嗦了，看代码吧！、

package com.hive.client;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

public class HiveClientUDF {
	private static String driverName = "org.apache.hive.jdbc.HiveDriver";
    private static String url = "jdbc:hive2://192.168.150.162:10000/default";
    private static String sql = "";
    private static ResultSet res;
	public static void main(String[] args) throws SQLException, ClassNotFoundException {
		// TODO Auto-generated method stub

		 Connection conn = null;
         Class.forName(driverName);
		 //默认使用端口10000, 使用默认数据库，用户名密码默认  hadoop 服务器登录用户名  dh!123456登录密码
         conn = DriverManager.getConnection(url, "hadoop", "dh！123456");
         String tableName = "vehicle_pass";
	   	 Statement stmt = conn.createStatement();
	     //将cityudf.jar加入到HIVE类路径下
		 sql = "add jar /home/hadoop/cityudf.jar";
   	     stmt.execute(sql);
   	     //加入到classpath下
   	     sql = "create temporary function cityudf as 'com.hive.utf.CityUDF'";
   	     stmt.execute(sql);
   	     //使用自定义UDF cityudf
	   	 sql = "select  key,kkNO,cityudf(key) as city from " + tableName;
         System.out.println("Running:" + sql);
	     res = stmt.executeQuery(sql);
	     System.out.println("执行“select * query”运行结果:");
	     while (res.next()) {

	         System.out.println(res.getString(1) + "\t" +":" + res.getString(3));

	      }
	   	  stmt.close();
	   	  conn.close();
	}

}

运行结果：

1522301_20150417103242404_黑A01BCI	:哈尔滨
1522301_20150417103242494_黑A013AA	:哈尔滨
1522301_20150417103242614_黑A01GHI	:哈尔滨
1522301_20150417103242616_黑A01GLJ	:哈尔滨
1522301_20150417103242617_黑A01E5G	:哈尔滨
1522301_20150417103242623_黑A01HDK	:哈尔滨
1522301_20150417103242625_黑A018MM	:哈尔滨
1522301_20150417103242758_黑A015KD	:哈尔滨