by Dinesh Thakur Category: Servlet with MySql Database

This Function will return that the given value is True or false.

The first i make a table in database named 'dbase’ with the required fields and value in it, database is been created within the reference of mySql(php myAdmin). Then i import all the required java packages from java library according to the program need. I made a class named 'MySqlISOPERATORFunction' completely extends 'HttpServlet'. Then i use the serviceMethod() which use to getting request from doGet()Method. Here i loaded all the required drivers for database accessing. After that, i declare mandatory variables for database conditions. Like i declare 'Connection' this variable will use to create a link between database and the java code. The other one will be the 'resultSet' this will be the responsible for the fetching value from the selected columns and rows. The next variable will be the 'preparedStatement' this variable is been used to executing the selected query like executeQuery() as (SELECT 9 IS TRUE).now here i use doGet()method which will bring the output on web browser.

Now i used some kind of 'HTML' code and tags that will present the output in a tabular form on a web browser.

import java.io.IOException;

import java.io.PrintWriter;
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 MySqlISOPERATORFunction extends HttpServlet
 {
      public void service(HttpServletRequest rq, HttpServletResponse rp)throws IOException, ServletException
       {
            rp.setContentType("text/html");
            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;
            try
             {
                   Class.forName(driver);
                   con = DriverManager.getConnection(url,uid,psw);
                   ps=con.prepareStatement("SELECT 9 IS TRUE");
                   rs = ps.executeQuery();
                String title = "Using IS OPERATOR 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</th>\n"+ "</body> </html>");
                  while(rs.next())
                      {
                           String val = rs.getString(1);
                        disp.println("<tr><td align=\"center\">" + val +"</td></tr>" );  
                      }      
             }        
                        catch(Exception e) 
                              {
                                  e.printStackTrace();
                              }
                                  disp.close();
     }
                         public void doPost(HttpServletRequest rq,HttpServletResponse rp)throws IOException,ServletException
                           {
                                     doGet(rq,rp);
                           }
  }
Web.xml
 
<servlet>
   <servlet-name>MySqlISOPERATORFunction</servlet-name>
   <servlet-class>MySqlISOPERATORFunction</servlet-class>
</servlet>
<!-- servlet mapping -->
<servlet-mapping>
   <servlet-name>MySqlISOPERATORFunction</servlet-name>
   <url-pattern>/MySqlISOPERATORFunction</url-pattern>
</servlet-mapping>




About Dinesh Thakur

Dinesh ThakurDinesh Thakur holds an B.SC (Computer Science), 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.



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