As with PHP, in Perl too, you first need to send the correct MIME type to the browser. Here’s how to do it.

print "Content-type: text/vnd.wap.wml\n\n";

print "<?xml version=\"1.0\"?>\n";

print "<!DOCTYPE wml PUBLIC \"-//WAPFORUM//DTD WML 1.1//EN\"\"http://www.wapforum.org/DTD/wml_1.1.xml\">\n\n";

….. Put your content here…..

Using Java servlets

Dynamic WML documents can be easily developed using Java servlets. Once you know the WML syntax, building WAP applications using Java servlets can be an easy task. Just set content type in your class and you can then send WAP tags. The line

Response.setContentType("text/vnd.wap.wml");

defines the WAP MIME type to the browser. This is followed by

import java.io.*;

import javax.servlet.*;

import javax.servlet.http.*;

public class MobileDate extends HttpServlet {

public void service (HttpServletRequest request, HttpServletResponse

response) throws ServletException, IOException {

To set the content type for your wireless data:

response.setContentType("text/vnd.wap.wml");

PrintWriter out = response.getWriter();

Now, you can write what you would like to display on the user’s screen:

out.println("<?xml version=\"1.0\"?>");

out.println("<!DOCTYPE wml PUBLIC \"-//WAPFORUM//DTD WML 1.1//EN\"");

out.println(" \"http://www.wapforum.org/DTD/wml_1.1.xml\">");

out.println("<wml>");

out.println("<card title=\"Hello\">");

out.println(" <p align=\"center\">");

out.println("java with wap<br/>");

out.println("</p>");

out.println("</card>");

out.println("</wml>");

}

}

WAP pages are organized as a deck of cards, each card being one display page. There is a limit to the size of a deck of WAP cards (all that is between <wml> and </wml>). The size depends on the WAP browser, and should not exceed the following limits.

(To be continued next month)
Gaurav Bhatnagar is a WAP project leader at rkmdaes.com