eclipse 访问 hive1.2.1

参考链接1.http://www.iteblog.com/archives/846

操作实际参考代码:http://sunhs.sinaapp.com/?p=343

配置eclipse 搞1天, 不管怎样导入包一直提示DriverManager not found exception:

注意1:要导入的包hive1.2.1里面的一个$HIVE_HOME/lib/slf4j-api-1.6.1.jar 应该没有,要到hadoop/share/hadoop/common/lib 下面导入以下2个代替,

/usr/local/hadoop/share/hadoop/common/lib/slf4j-log4j12-1.7.5.jar

/usr/local/hadoop/share/hadoop/common/lib/slf4j-api-1.7.5.jar

注意2:虽然hive创建在mysql 的元数据库是hive,但是我们这里写的数据库只能写default,不能写hive,不然怎么调整mysql 都会提示数据库不存在,

但是改成default 之后,在mysql 中hive 数据库下面的TBLS表里可以查询到下面代码运行所创建的testhivedrivertable表.

附: 在eclipse 运行代码的过程中,在hive --service hiveserver2 terminal 终端可以看到程序如map 进程.

原因如下:

上面是用Java连 接HiveServer，而HiveServer本身存在很多问题（比如：安全性、并发性等）；针对这些问题，Hive0.11.0版本提供了一个全新的 服务：HiveServer2，这个很好的解决HiveServer存在的安全性、并发性等问题。这个服务启动程序在${HIVE_HOME}/bin /hiveserver2里面，你可以通过下面的方式来启动HiveServer2服务：

$HIVE_HOME/bin/hiveserver2

也可以通过下面的方式启动HiveServer2

$HIVE_HOME/bin/hive --service hiveserver2

两种方式效果都一样的。但是以前的程序需要修改两个地方，如下所示：

private static String driverName = "org.apache.hadoop.hive.jdbc.HiveDriver";
改为
private static String driverName = "org.apache.hive.jdbc.HiveDriver";
 
Connection con = DriverManager.getConnection(
                           "jdbc:hive://localhost:10002/default", "wyp", "");
改为
Connection con = DriverManager.getConnection(
                           "jdbc:hive2://localhost:10002/default", "wyp", "");

这里顺便说说本程序所依赖的jar包，一共有以下几个(版本不同,但是匹配类似就行)：

hadoop-2.2./share/hadoop/common/hadoop-common-2.2..jar
$HIVE_HOME/lib/hive-exec-0.11..jar
$HIVE_HOME/lib/hive-jdbc-0.11..jar
$HIVE_HOME/lib/hive-metastore-0.11..jar
$HIVE_HOME/lib/hive-service-0.11..jar
$HIVE_HOME/lib/libfb303-0.9..jar
$HIVE_HOME/lib/commons-logging-1.0..jar
$HIVE_HOME/lib/slf4j-api-1.6..jar

代码

package getConnect;
 
import java.sql.SQLException;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.Statement;
import java.sql.DriverManager;
 
public class HiveJdbcClient {
  private static String driverName = "org.apache.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);
    }
    //replace "hive" here with the name of the user the queries should run as
    Connection con = DriverManager.getConnection("jdbc:hive2://192.168.2.35:10000/default", "hadoop", "1234");
    Statement stmt = con.createStatement();
    String tableName = "testHiveDriverTable";
    stmt.execute("drop table if exists " + tableName);
    stmt.execute("create table " + tableName + " (key int, value string)");
    // show tables
    String sql = "show tables '" + tableName + "'";
    System.out.println("Running: " + sql);
    ResultSet 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) + "\t" + res.getString(2));
    }
 
// 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 = "/usr/local/hive/examples/files/kv1.txt";
sql = "load data local inpath '" + filepath + "' into table " + tableName;
System.out.println("Running: " + sql);
stmt.execute(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)) + "\t" + res.getString(2));
}
 
// 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));
}}}