how can i call a class java class from servlet

Question

i hava a html page and hello is my servlet

 <html>
 <body>
 <form action="http://localhost:8080/nitin/jsnipop/hello" method="post">
   <input type="text" id="foo" name="foo">
 <input type="submit" value="Send" name="submit" id="submit">
</form>
 </body>
 </html>

and my servlet is

public class hello  extends HttpServlet{
/**
 * 
 */
private static final long serialVersionUID = 1L;

public void doPost(HttpServletRequest req,HttpServletResponse res)throws ServletException,IOException
{
    res.setContentType("text/html");
    PrintWriter pw=res.getWriter();
    String foo=req.getParameter("foo");   
    pw.println("Welcome "+foo);
}
}

now i want to send foo string variable on client side and set this as a user name my client class name is ser.java please help

score 0 · Answer 1 · edited May 23 '17 at 12:08

0

Note:

Don't write anything in response stream once request is forwarded to some one else.

There is no meaning of below line:

pw.println("Welcome "+foo);

because now the response is driven by forwarded JSP/Servlet/HTML.

Classes that is shared between client and server must be placed under shared folder.

Steps to follow:

Create an object of Model class that is placed under shared folder and just a POJO class.
Set the properties in the object such as username etc.
Set the object as request attribute.
Forward the request to some one else
Simply read it in forwarded JSP/Servlet.

Please have a look at below links to set and get the request attribute

Access value between two JSP with JSTL

Sample code:

hello Servlet (server side)

// get the parameter from the request
String foo=req.getParameter("foo");

// create an object of Model class
Model model = new Model();

// Set the properties in the object
model.setUserName(foo);

// set the object as request attribute
req.setAttribute("model",model);

// forward the request to some one else
rd.forward(req, res);

In forwarded JSP (using Scriplets)

<!-- Simply read it here -->
<%com.x.y.shared.Model model = request.getAttribute("model");%>

Model class (shared folder)

public class Model implements IsSerializable, Serializable{
    private String userName;

    public Model(){} // no-arg constructor
    // getter & setter
}

edited May 23 '17 at 12:08

Community

1
1

answered May 09 '14 at 12:05

Braj

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i want to set this in a text box and my have onmodule load function is this work – May 09 '14 at 12:09
I have already shared you code. What was the issue with that code? – Braj May 09 '14 at 12:09
i can't use jsp help me with some other option. It will be vry kind of you – May 09 '14 at 12:13
OK please tell me what is `rd` is here? where your request is forwarded? – Braj May 09 '14 at 12:15
its a object of dispeture class – May 09 '14 at 12:17
I know it but where is it dispatching the request? – Braj May 09 '14 at 12:18
Tell me the flow. **HTML -> Servlet -> ?(What next here)** – Braj May 09 '14 at 12:19
my flow is HTMl -> Servlet-> model.java ( its a client Javaclass) – May 12 '14 at 05:26
after following the above procedure i face (java.lang.NoClassDefFoundError: com/google/gwt/core/client/EntryPoint) this exception. – May 12 '14 at 05:57
Please search on Google. It's very common issue in GWT. – Braj May 12 '14 at 07:09
Sorry you can't do it. Model is just like a DTO (Data Transfer Object) that is used to transfer the data between server and client. HTML -> Servlet(set model as request attribute) -> HTML/JSP(read model from the request) – Braj May 12 '14 at 07:13

how can i call a class java class from servlet

1 Answers1