Note: this document is work in progress and not complete at the moment

[Edit]How can I integrate Google Web Toolkit modules in a new Special: page

[Edit]Introductory articles

• Build an Ajax application using Google Web Toolkit, Apache Derby, and Eclipse, Part 1
• Introduction to the Google Web Toolkit
• Google Web Toolkit - Build AJAX apps in the Java language

[Edit]An AJAX calculator example

My example GWT module is an AJAX calculator called org.matheclipse.gwt.Calc which is separately developed in the GWT hosted mode and should now be included into a new JAMWiki Special:Calc page.

In the main GWT EntryPoint in the method org.matheclipse.gwt.client.Calc#onModuleLoad() we can distinguish between non-hosted mode and hosted mode with the GWT.isScript() method. In the onModuleLoad() method we also create the main calculator GUI panel and insert it into a prepared "slot1" in calc.jsp (see below).

public void onModuleLoad() {
   CALC_SERVICE = (CalcServiceAsync) GWT.create(CalcService.class);
   ServiceDefTarget target = (ServiceDefTarget) CALC_SERVICE;
   if (GWT.isScript()) {
     String url = GWT.getModuleBaseURL();
     url += "calc"; 
     target.setServiceEntryPoint(url);
   } else {
     target.setServiceEntryPoint("/calc");
   }
 ...
   // Create a panel for the GUI and insert it into a prepared "slot1" in cals.jsp
   RootPanel slot1 = RootPanel.get("slot1");
   slot1.add(panel);
 ...

[Edit]Creating a new Special:Calc page

• Modify the /WEB-INF/jamwiki-servlet.xml file to add a mapping and a servlet handler. The mapping is the URL pattern (such as <prop key="/**/Special:Calc">Calc</prop>) and the handler links the mapping with a servlet (such as <bean id="Calc" class="org.jamwiki.servlets.CalcServlet" />).
• Make sure JAMWiki recognizes your page as an existing special page by adding the URL pattern to /WEB-INF/classes/pseudotopics.properties (for JAMWiki versions prior to 0.5.0) or by adding a pseudotopic entry to /WEB-INF/classes/jamwiki-configuration.xml (for JAMWiki 0.5.0 or later).
  Example: <pseudotopic><name>Special:Calc</name></pseudotopic>.
• Create the servlet that you specified in the jamwiki-servlet.xml file ("org.jamwiki.servlets.CalcServlet"). The servlet should extend JAMWikiServlet:

protected ModelAndView handleJAMWikiRequest(HttpServletRequest request,
         HttpServletResponse response, ModelAndView next, WikiPageInfo pageInfo)
         throws Exception {
   pageInfo.setPageTitle(new WikiMessage("calc.title"));
   pageInfo.setAction(WikiPageInfo.ACTION_CALC);
   pageInfo.setSpecial(true);
   return next;
 }

• Add a description into ApplicationResources.properties

calc.title=AJAX online calculator

• Add an action for the servlet to org.jamwiki.servlets.WikiPageInfo:

...
 public static final int ACTION_CALC = 999;
 ...
 public boolean getActionCalc() {
     return (this.action == ACTION_CALC);
 }

• Copy a first WEB-INF/jsp/calc.jsp for example from the WEB-INF/jsp/search.jsp
• Process the action for your servlet and display the page by modifying wiki.jsp appropriately:

<c:when test="${pageInfo.actionCalc}">
   <jsp:include page="calc.jsp" flush="true" />
 </c:when>

[Edit]Integrating the GWT module

In a separated GWT project I compiled all GWT files into the \www\org.matheclipse.gwt.Calc directory. These files must now been copied into a JAMWiki subdirectory.

For a better organization all compiled (static) GWT files in this example go into subdirectory:

/wiki/static

and the main gwt.js is stored in

/wiki/static/gwt.js

• The compiled GWT files are copied from the

/www/org.matheclipse.gwt.Calc 

directory into the directory

/wiki/static/org.matheclipse.gwt.Calc

• In the /WEB-INF/jsp/top.jsp file I added this line in the header section:

<meta name='gwt:module' content='/wiki/static/org.matheclipse.gwt.Calc=org.matheclipse.gwt.Calc'>

• Description of the new /WEB-INF/jsp/calc.jsp file

<%@ page errorPage="/WEB-INF/jsp/error.jsp"
    contentType="text/html; charset=utf-8"
 %>
 <%@ include file="page-init.jsp" %>
 <!-- GWT CSS styles follow in this section -->
 <style type="text/css">
   ... 
 </style>
 <script language='javascript' src='/wiki/static/gwt.js'></script>
    <iframe id='__gwt_historyFrame' style='width:0;height:0;border:0'></iframe>
    <div id="loadingWait">Loading...</div>
       <table align="left" verticalalign="top">
	<tr><td id="slot1"></td></tr>
       </table>

• Copy all necessary *.jar files for yor application into the WEB-INF/lib directory
• Copy GWT gwt-servlet.jar into the WEB-INF/lib directory
• Modify JAMWiki's web.xml servlets mapping

...
 <servlet>
   <servlet-name>calculator</servlet-name>
     <servlet-class>org.matheclipse.gwt.server.CalcServiceImpl</servlet-class>
   <load-on-startup>1</load-on-startup>
 </servlet>
 ...
 <servlet-mapping>
   <servlet-name>calculator</servlet-name>
   <url-pattern>/static/org.matheclipse.gwt.Calc/calc</url-pattern>
 </servlet-mapping>