controller.jsp

此程序都是企业级 的数据库开发程序 全面揭示了JAVA对数据库的操作

  <%@page import="java.util.*"%>
  <%@page import="java.io.*"%>
  <%@page import="org.w3c.dom.Document"%>
  <%@page import="mvc.*"%>

  <%

      /*
        The MVC framework shown for this chapter use the Xalan XSLT
        processor and Xerces XML parser. Xalan and Xerces are freely
        available from the http://xml.apache.org. The MVC framework built
        in this chapter uses version 2.2.D6 of the Xalan XSLT processor and
        version 1.3 of the Xerces XML parser. In controller.jsp the
        org.w3c.dom.Document class comes from the Xerces jar file 
        (xerces.jar).
      */


      /*
        The controller JSP is the controller piece of the MVC Framework.
        This piece will first try and retrieve the name of the XSL file the
        user wants to view. After the xslFileName is retrieved it will
        instantiate the Request handler. The request handler will invoke the
        appropriate model. The model will return an XML document with all of
        the data to be presented to the end-user. The controller.jsp will
        then return the JspWriter out variable, the data returned from the
        RequestHandler, and the name of the XSL file that will be used to
        present the data. The XSLTManager will carry out the merging of the
        XSL and XML document.
      */
  try{
    String requestValue = request.getParameter("Request");
    String actionValue  = request.getParameter("Action");

   /*Step 1 - Retrieve the name of the XSL file that is going to be used*/
    String  xslFileName =
                        MVCHelper.getXSLFileName(requestValue,actionValue);

    if (xslFileName == null){
      throw new Exception("Unable to locate an XSL file that matches the " +
                          "request and action requested. Request: " +
                           requestValue + " , Action: " + actionValue);
    }

    /*Step 2 - Instantiate the RequestHandler and process the user's request
    */
    RequestHandler requestHandler = new RequestHandler();
    Document returnedData = requestHandler.process(request);

    /*Step 3 - Take the Document retrieved from the requesthandler and
               transform it to HTML
    */
    XSLTManager xsltManager = new XSLTManager();
    xsltManager.transformOutput(out, returnedData, xslFileName);
  } catch(Exception e){
    MVCHelper.buildErrorPage(e, out);
  }
  %>