Re: [Jython-dev] servlet problem self.getInitParameterNames() under PyServlet wrapper

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[Brian Zhou]

>Hello list,
>
>Following http://groups.yahoo.com/group/jpython/message/3714 I succeeded
>making servlet running under PyServlet wrapper/handler on win2k tomcat3.2.1.
>So far so good, I can run simple script like:
>
>import sys, java, javax
>
>class hello(javax.servlet.http.HttpServlet):
>   def doGet(self, req, res):
>      res.setContentType("text/html");
>      out = res.getOutputStream()
>      out.println("""\
><html>
><head><title>Hello World</title></head>
><body>Hello World!
><P>
>current server time is: %s
></P>
></body>
></html>
>""" % (java.util.Date()))
>      out.close()
>      return
>
>Or even dynamicly generate PNG graph thanks to the new javax.imagio package
>from Sun. I don't expect any difficulty hooking up with database using JDBC.
>
>However, when trying to port SnoopServlet from java to jython, I found that
>PyServlet really doesn't handover any instant variables to the jython
>HttpServlet subclass except (request, response). So
>
>    enum = self.getInitParameterNames()
>
>will got a NullPointerException. Any operation involve self.attribute like
>self.getServletContext() will also fail. I don't think jythonc compiled
>classes will have this problem because the jython servlet handle service()
>directly bypassing PyServlet.
>
>So my questions are:
>
>1. Am I missing anything? Any misunderstanding of the API?

I'm no expert on servlets, but I think the servlet must be initialized
somehow. By adding 

            servlet.init(getServletConfig());

to PyServlet.loadServlet(), I managed to avoid the NPE in
getInitParameterNames(). 

regards,
finn