Map Reduce error for concurrent user from Java application to access Apache Hive
We have a user interface based on Java. This application connects Hive as data source. Please find the product version of Apache Hive below. Application is working fine when single user has login with the application to access data from Hive. It gives error while concurrent users login to same application and access the Hive data..
apache-hive-2.3.7
db-derby-10.14.2.0
hadoop-2.10.0
Further investigation –
The authentication mechanism of Hive is NOSASL. We did a small mutli threaded java application for debugging. Please find Java code and log for your analysis.
Thanks in advance for your help!!
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
public class MapReduceThreadClass implements Runnable {
String name;
Thread t;
String query;
MapReduceThreadClass (String thread,String query){
name = thread;
this.query=query;
t = new Thread(this, name);
System.out.println("New thread: " + t);
t.start();
}
@Override
public void run() {
Connection conn = null;
try {
Class.forName("org.apache.hive.jdbc.HiveDriver");
String url = "jdbc:hive2://XX.XX.XX.XX:10000/test1;auth=noSasl";
conn = DriverManager.getConnection(url);
PreparedStatement ps=conn.prepareStatement(query);
System.out.println("thread "+Thread.currentThread().getName()+"before query execution");
ResultSet rs=ps.executeQuery();
if(rs.next()) {
System.out.println("thread "+Thread.currentThread().getName()+"::"+rs.getString(1));
System.out.println("thread "+Thread.currentThread().getName()+"::"+"Got it!");
}
} catch (Exception e) {
e.printStackTrace();
throw new Error("Problem", e);
} finally {
try {
if (conn != null) {
conn.close();
}
} catch (SQLException ex) {
System.out.println(ex.getMessage());
}
}
// TODO Auto-generated method stub
}
}
----
public class MapReduceMain {
public static void main(String[] args) {
//18
for(int i=0;i<Integer.parseInt(args[0]);i++)
{
new MapReduceThreadClass(i+1+"",args[1]);
}
// TODO Auto-generated method stub
}
}
