Refresh a Web Page Using In Servlet

In this section, you will learn how to refresh servlets page.

Refresh a Web Page Using In Servlet

Refresh a Web Page Using In Servlet

     

In this simplified example we develop an application to Refresh a web Page using Servlet. We create two file timer.html and timer.java. When a web page ("timer.html") run on browser then it will call to Servlet ("timer.java") and refresh this web page and print the current Date and Time after 10 sec on the browser as a output.

Step 1: Create a web page(timer.html) to call a Servlets.

timer.html 

<HTML>
 <HEAD>
  <TITLE>Refresh Servlet Timer</TITLE>
  <META NAME="Generator" CONTENT="EditPlus">
  <META NAME="Author" CONTENT="">
  <META NAME="Keywords" CONTENT="">
  <META NAME="Description" CONTENT="">
  <style type="text/css">
A:link {text-decoration: none;
    padding: 3px 7px;
    margin-right: 3px;
 
    border-bottom: none;
 
    color: #2d2b2b;  }
A:visited {text-decoration: underline;
    padding: 3px 7px;
    margin-right: 3px;
   
  
    color: #2d2b2b; }
A:active {text-decoration: none}
A:hover {text-decoration: none;
    padding: 3px 7px;
    margin-right: 3px;
    border: 0px;

    color: #2d2b2b; }
</style>

 
 </HEAD>

 <BODY>
 <br><br><br> <br><br><br>
 <table width="200px" height="100px" 
  align="center" bgcolor="#BBFFFF" border=0>
 <tr> 
      <td style="text-align:top;" valign="middle" 
      align="center" border=0>
   <a href="timer" ><b>Refresh Servlet Timer</b></a>
    </td>
 </tr>

 </BODY>
</HTML>

 

Step 2:Create a Servlet (timer.java) which refresh the page after every 10 seconds. 

import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
import java.util.*;


public class timer extends HttpServlet{ 
 public void doGet(HttpServletRequest request, 
  HttpServletResponse response)
  throws 
ServletException,IOException{
  response.setContentType("text/html");
  PrintWriter out = response.getWriter();
  Date now = new Date(); // The current date/time
  out.println("<html>");
  out.println("<head><title> Time Check </title></head>");
  out.println("<body>");
  out.println
  ("<table  width='100%' align='center' valign='top'>");
  out.println("<tr>");
  out.println("<td>&nbsp;");
  out.println("</td>");
  out.println("</tr>");
  out.println("</tr>");
  out.println("<tr>");
  out.println("<td valign='top' align='center' valign='top'>");
  out.println
   ("<p style='color:#00000;font-size:20pt'>"+
  "<b>The Time is Refresh After 10 Seconds.</b></p>");
  out.println("<td>");
  out.println("</tr>");
  out.println("<tr>");
  out.println("<td>&nbsp;");
  out.println("</td>");
  out.println("</tr>");
  out.println("</tr>");
  out.println("<tr>");
  out.println("<td>&nbsp;");
  out.println("</td>");
  out.println("</tr>");
  out.println("</tr>");
  out.println("<tr>");
  out.println("<td style='background-color:#C6EFF7;color:blue;'"+
  " width='50' align='center'>");
  out.println("<b>The current time is: " + now + "</b>");
  out.println("</td>");
  out.println("</tr>");
  out.println("<table>");
  out.println("</body></html>"); 
  response.setHeader("Refresh", "10");
  
  }
}

Save the above file into "timer\WEB-INF\classes" directory.

Step 3: Mapping the servlet (timer.java) in to web.xml file:

<?xml version="1.0" encoding="ISO-8859-1"?>
<web-app xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
version="2.5">

<display-name>Welcome to Tomcat</display-name>
<description>
Welcome to Tomcat
</description>
<servlet>
<servlet-name>timer</servlet-name>
<servlet-class>timer</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>timer</servlet-name>
<url-pattern>/timer</url-pattern>
</servlet-mapping>

</web-app>

Step 4: Now compile the java code using javac command from command prompt.

Step 5: Start tomcat and type http://localhost:8080/timer/timer.html in the browser and Click on Text Link "Refresh Servlet Timer" . Your browser should display the Current Time and Refresh after 10 seconds.  

Successful Output of the program:

 

Download the full web application shows here.

Download the application