Here is an example on how to retrieve the home interface of a bean named Region from a Servlet and then create a new instance of this bean:
import java.io.*;
import javax.naming.Context;
import javax.naming.InitialContext;
import javax.rmi.PortableRemoteObject;
import javax.servlet.*;
import javax.servlet.http.*;
public class RegionServlet extends HttpServlet
{
/**
* Called on a GET request for this servlet
*
* @param request a <code>HttpServletRequest</code> value
* @param response a <code>HttpServletResponse</code> value
* @exception IOException if an error occurs
* @exception ServletException if an error occurs
*/
public void doGet(HttpServletRequest request,
HttpServletResponse response) throws IOException, ServletException
{
private PrintWriter out;
response.setContentType("text/html");
try
{
out = reponse.getWriter();
}
catch (IOException ioe)
{
ioe.printStackTrace();
}
out.println("<!doctype html public
"-//w3c//dtd html 4.0 transitional//en">");
out.println("<html>");
out.println("<body>");
out.println("RegionServlet - Looking for the initial context<br>")
Context initialContext = null;
try
{
initialContext = new InitialContext();
}
catch (Exception e)
{
out.println("RegionServlet - Cannot get initial context for JNDI: "
+e+"<br>");
return ;
}
out.println("RegionServlet - Looking up bean's home interface<br>")
RegionHome home;
try
{
home = (RegionHome)PortableRemoteObject.narrow(
initialContext.lookup("java:comp/env/ejb/RegionHome"),
RegionHome.class);
}
catch (Exception e)
{
out.println("RegionServlet - Cannot lookup home interface: "
+e+"<br>");
return ;
}
out.println("RegionServlet - Creating a new bean instance<br>")
Region bean;
try
{
bean = home.create();
}
catch (Exception e)
{
sp.printHTML("RegionServlet - Error while creating new bean instance: "
+e+"<br>");
return ;
}
... here you can call any method defined in the bean
remote interface (example: bean.doSomething(...);) ...
out.println("</body>\n");
out.println("</html>\n");
}
} |