This function will return the value as Day Of week (1-7). first i made a database named ‘dbase’ within the reference of mySql(php myAdmin).i import all the required java packages from java library according to requirement of program. Then i made a class named ‘MySqlDayOfWeek’ which extends ‘HttpServlet’. Then after i use service()Method that will getting request from the doGet() for output on the web browser. Then after i loaded all the required drivers for database accessing.
Here i need to declare some variable which are mandatory for database using like i declare ‘connection’ this will be responsible for the create a link or bridge between the database and the java code. Then i declare ‘resultSet’ this variable will use to get the value from the selected column and rows. The last one will be the ‘preparedStatement’ that will use to executing the selected query like executeQuery() as (Select DAYOFWEEK(‘2014-05-31’)).here i use the doGet()Method for the output on web browser.
I use ‘HTML’ code and tags in last move to get output in tabular form on the 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 MySqlDayOfWeek 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 DAYOFWEEK('2014-05-31') AS dw");
rs = ps.executeQuery();
String title = "Using Day Of Week 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>Day</th>\n"+ "</body> </html>");
while(rs.next())
{
String curr = rs.getString(1);
disp.println("<tr><td align=\"center\">" + curr +"</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>MySqlDayOfWeek</servlet-name>
<servlet-class>MySqlDayOfWeek</servlet-class>
</servlet>
<!-- servlet mapping -->
<servlet-mapping>
<servlet-name>MySqlDayOfWeek</servlet-name>
<url-pattern>/MySqlDayOfWeek</url-pattern>
</servlet-mapping>