Program Insert Rows into a database table using Multithreading in Java

import java.sql.Connection;

import java.sql.Date;

import java.sql.DriverManager;

import java.sql.PreparedStatement;

import java.sql.SQLException;

import java.sql.Timestamp;

import java.util.Calendar;

public class Publisher implements Runnable {

               

                static int i=1;

                static Connection c;

               

                static Thread t1,t2;

                public static void main(String[] args) {

                                // TODO Auto-generated method stub

                               

                                try {

                                                 c=DriverManager.getConnection("jdbc:postgresql://localhost:5432/postgres", "postgres", "oracle");

                                                 

                                                 Publisher p1=new Publisher();

                                                  t1=new Thread(p1);

                                                  t1.setName("A");

                                                  t2=new Thread(p1);

                                                  t2.setName("B");

                                                 t1.start();

                                                 t2.start();

                                               

                                               

                                } catch (SQLException e) {

                                                // TODO Auto-generated catch block

                                                e.printStackTrace();

                                }

                }

                @Override

                public  void run() {

                                // TODO Auto-generated method stub

                                 PreparedStatement pstmt;

                                String ins_into_pub_log="Insert into trx_pub(trx_id,curr_date,pub_code,sub_code)values(nextval('trx_id_1sq'),current_date,?,?);";

                                 

                                               

                                                try {

                                                                pstmt=c.prepareStatement(ins_into_pub_log);

                                while(i<150){

                pstmt.setString(1,Thread.currentThread().getName());                

                pstmt.setString(2, "SUB");          

                                                                i++;

                                                                pstmt.execute();

                                                               

                                }

                               

                                                } catch (SQLException e) {

                                                                // TODO Auto-generated catch block

                                                                e.printStackTrace();

                                                }

                                }

                }

                                                         Output of this program: