HIVE jdbc访问程序--Eclipse环境（hive-0.12.0 + hadoop-2.4.0集群）

一、Eclipse 新建Other-》Map/Reduce Project工程

工程自动包含了相关hadoop的jar包，

另外还需分别导入以下hive和连接mysql的jar包：

hive/lib/*.jar

mysql-connector-java-5.1.24-bin.jar

二、启运HiveServer

命令：bin/hive --service hiveserver &

曾经执行多次这个命令没成功后，报错：Could not create ServerSocket on address 0.0.0.0/0.0.0.0:10000.

解决办法：启动时，指定端口号，命令

bin/hive --service hiveserver -p 10002

如果没报错就不用理会，但下面代码中的端口号要改为默认的10000，与这里的一致。

三、Eclipse中java测试代码

如果新建工程时不时选择hadoop工程，会报错：Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/hadoop/io/Writable

解决办法：这是因为一下hadoop的包没有加进来，重新建一个工程，工程类型选择Other-》Map/Reduce Project工程，自动就包含了hadoop开发环境

另需先在/home/hadoop/file/目录下准备user_info.txt文件，内容如下( 分割符)

1001　　jack    30
1002　　tom    25
1003　　kate    20

//--------------HiveTest .java-----------------

package test;

import java.sql.SQLException;  

import java.sql.Connection;  

import java.sql.ResultSet;  

import java.sql.Statement;  

import java.sql.DriverManager;  

 

public class HiveQuery {  

  private static String driverName = "org.apache.hadoop.hive.jdbc.HiveDriver";  

 

  /**

 * @param args

 * @throws SQLException

   */  

  public static void main(String[] args) throws SQLException {  

      try {  

      Class.forName(driverName);  

    } catch (ClassNotFoundException e) {  

      // TODO Auto-generated catch block  

      e.printStackTrace();  

      System.exit(1);  

    }  

    Connection con = DriverManager.getConnection("jdbc:hive://192.168.1.200:10002/default", "", "");  

    Statement stmt = con.createStatement();  

    String tableName = "testHiveDriverTable";  

    stmt.executeQuery("drop table " + tableName);  

    ResultSet res = stmt.executeQuery("create table " + tableName + " (id int, name string, age string) row format delimited fields terminated by ' ' lines terminated by ' '");  

    // show tables  

    String sql = "show tables '" + tableName + "'";  

    System.out.println("Running: " + sql);  

    res = stmt.executeQuery(sql);  

    if (res.next()) {  

      System.out.println(res.getString(1));  

    }  

    // describe table  

    sql = "describe " + tableName;  

    System.out.println("Running: " + sql);  

    res = stmt.executeQuery(sql);  

    while (res.next()) {  

      System.out.println(res.getString(1) + " " + res.getString(2)+ " " + res.getString(3));  

    }  

 

    // load data into table  

    // NOTE: filepath has to be local to the hive server  

    // NOTE: /tmp/a.txt is a ctrl-A separated file with two fields per line  

    String filepath = "/home/hadoop/file/user_info.txt";  

    sql = "load data local inpath '" + filepath + "' into table " + tableName;  

    System.out.println("Running: " + sql);  

    res = stmt.executeQuery(sql);  

 

    // select * query  

    sql = "select * from " + tableName;  

    System.out.println("Running: " + sql);  

    res = stmt.executeQuery(sql);  

    while (res.next()) {  

      System.out.println(String.valueOf(res.getInt(1)) + " " + res.getString(2) + " " + res.getString(3));  

    }  

 

    // regular hive query  

    sql = "select count(1) from " + tableName;  

    System.out.println("Running: " + sql);  

    res = stmt.executeQuery(sql);  

    while (res.next()) {  

      System.out.println(res.getString(1));  

    }  

  }  

} 

//------------end---------------------------------------------

四、显示结果

Running: show tables 'testHiveDriverTable'

testhivedrivertable

Running: describe testHiveDriverTable

id                  int                

name             string              

age               string              

Running: load data local inpath '/home/hadoop/file/user_info.txt' into table testHiveDriverTable

Running: select * from testHiveDriverTable

1001 jack 30

1002 tom 25

1003 kate 20

Running: select count(1) from testHiveDriverTable

3