by Dinesh Thakur Category: Servlet with MySql Database

The Function 'CONCAT' will add Two String with each other.

In the first instance i make a table  with required Fields and values into the database named 'dbase' within the reference of mySql(php myAdmin).then i import all the required java packages from java library. Then i make a class named 'MySqlConcatFunc' which extends the 'HttpServlet'. I use serviceMethod() which will bring the request from doGet()Method for output on the web browser. After that i loaded all the required drivers for database accessing. Here i declare some mandatory variables like i declare Connection (this variable will create a link between database and the java code). Then i use 'resultset' that will bring the value from the required columns and rows. i declare 'preparedStatement' that will responsible for the executing selected query like executeQuery() as (Select CONCAT('My','S','ql'). Then i use doGet()Method for getting output on the web Browser.

To Getting Output on web browser in a tabular form i use 'HTML' code and tags.


import java.sql.DriverManager;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class MySqlConcatFunc extends HttpServlet
   public void service(HttpServletRequest rq, HttpServletResponse rp)throws IOException, ServletException
      PrintWriter disp = rp.getWriter();
      String driver = "com.mysql.jdbc.Driver";
      String url = "jdbc:mysql://localhost/dbase";
      String uid = "root";
      String psw = "root";
      Connection con=null;
      PreparedStatement ps = null;
      ResultSet rs;
          con = DriverManager.getConnection(url,uid,psw);
          ps=con.prepareStatement("Select CONCAT('My','S','ql')");
          rs = ps.executeQuery();
              String title = "Using Concat Function";
          String docType ="<!doctype html public \"-//w3c//dtd html 4.0 " + "transitional//en\">\n";
              disp.println(docType + "<html>\n" + "<head><title>" + title + "</title></head>\n" +
          "<body bgcolor=\"#f4efef\">\n" + "<h1 align=\"center\">" + title + "</h1>\n" + "<ul>\n" +
              "<table width=\"50%\" border=\"1\" align=\"center\">\n" + "<th>Value Is </th>\n"+ "</body> </html>");
             String val = rs.getString(1);
                 disp.println("<tr><td align=\"center\">" + val +"</td></tr>" );  
                 catch(Exception e) 
                       public void doPost(HttpServletRequest rq,HttpServletResponse rp)throws IOException,ServletException
<!-- servlet mapping -->

About Dinesh Thakur

Dinesh ThakurDinesh Thakur holds an B.C.A, MCSE, MCDBA, CCNA, CCNP, A+, SCJP certifications. Dinesh authors the hugely popular blog. Where he writes how-to guides around Computer fundamental , computer software, Computer programming, and web apps. For any type of query or something that you think is missing, please feel free to Contact us.

Related Articles