How to make action or render request from the Adobe Flex

I built a sample portlet using concept of Single portlet refresh url to demonstrate how to make either a render or action request from the Adobe Flex. You can download the sample code for portlet and flex code

The sample application has a SPRInFlexPortlet, which has doView() and processAction() method, inside the doView() method it is checking if the caller == flex parameter is set if not then it assumes that this request is for the first render and forwards control to sprinflex.jsp page, if this request is made by the flex then it returns the request parameters in the string format.

The processAction() method sets a render parameter requestType == action to let us know that this request was made from the action phase

public class SPRInFlexPortlet extends javax.portlet.GenericPortlet {
  public void doView(RenderRequest request, RenderResponse response) 
  throws PortletException, IOException {
    // Set the MIME type for the render response
    response.setContentType(request.getResponseContentType());
    System.out.println("Entering SPRInFlexPortlet.doView()");
    if(request.getParameter("caller") == null){
      System.out.println("Request from portal, not flex");
      SPRUtil sprUtil = new SPRUtil();
      String renderUrl = sprUtil.getPortletRefreshUrl(request, response);
      String actionUrl = sprUtil.getPortletActionUrl(request, response);
      request.setAttribute("renderUl", renderUrl);
      request.setAttribute("actionUrl", actionUrl);
      getPortletContext().getRequestDispatcher("/sprinflex.jsp").include(request, response);
      return;
    }
    PrintWriter out = response.getWriter();
    out.println("Listing out parameters in the SPRFlexPortlet.doView()");
    Enumeration paramNames = request.getParameterNames();
    while(paramNames.hasMoreElements()){
      String paramName = paramNames.nextElement();
      System.out.println(paramName +" " + request.getParameter(paramName));
      out.println(paramName +" " + request.getParameter(paramName)+" ");
    }
    System.out.println("Got request for the first time");
  }
  public void processAction(ActionRequest request, ActionResponse response) 
  throws PortletException, java.io.IOException {
    System.out.println("Entering SPRInFlexPortlet.processAction");
    Enumeration paramNames = request.getParameterNames();
    while(paramNames.hasMoreElements()){
      String paramName = paramNames.nextElement();
      System.out.println(paramName +" " + request.getParameter(paramName));
      response.setRenderParameter(paramName, request.getParameter(paramName));
    }
    response.setRenderParameter("requestType", "action");
    System.out.println("Exiting SPRInFlexPortlet.processAction");
  }
}

The SPRInFlexPortlet method makes use of SPRUtil to calculate single window render and action url and forwards those values to the JSP. In the JSP i am returning those values from JavaScript method and also rendering HelloFlex object

<%@page language="java" contentType="text/html; charset=ISO-8859-1" 
pageEncoding="ISO-8859-1" session="false"%>
<%@taglib uri="http://java.sun.com/portlet" prefix="portlet"%>
<%@taglib 
uri="http://www.ibm.com/xmlns/prod/websphere/portal/v6.1/portlet-client-model" 
prefix="portlet-client-model"%>
<%@taglib uri="http://java.sun.com/portlet" prefix="portletx"%>
<portlet-client-model:init>
  <portlet-client-model:require module="ibm.portal.xml.*" />
  <portlet-client-model:require module="ibm.portal.portlet.*" />
</portlet-client-model:init>
<portlet:defineObjects />
<script type="text/javascript">
  function getRenderUrl(){
    console.log("Returning renderUrl");
    return "<%=renderRequest.getAttribute("renderUl")%>";
  } 
  function getProcessActionUrl(){
    console.log("Returning processActionUrl");
    return "<%=renderRequest.getAttribute("actionUrl")%>";
  } 
</script>
<object classid="clsid:D27CDB6E-AE6D-11cf-96B8-444553540000"
   id="HelloWorld" width="100%" height="100%"
   codebase="http://fpdownload.macromedia.com/get/flashplayer/current/swflash.cab">
   <param name="movie" value='<%= renderResponse.encodeURL(renderRequest.getContextPath() + "/HelloWorld.swf") %>' />
   <param name="quality" value="high" />
   <param name="bgcolor" value="#869ca7" />
   <param name="allowScriptAccess" value="sameDomain" />
   <embed src="<%= renderResponse.encodeURL(renderRequest.getContextPath() + "/HelloFlex.swf") %>" 
quality="high" bgcolor="#869ca7"
    width="100%" height="100%" 
name="HelloWorld" align="middle" play="true" 
loop="false" quality="high" allowScriptAccess="sameDomain"
    type="application/x-shockwave-flash" 
pluginspage="http://www.adobe.com/go/getflashplayer">
   </embed>
 </object>

The HelloFlex code is same as that of the Making resource request from portlet using Flex application, it demonstrates how to make a JavaScript method call to first get the URL and then to make a HTTP call to get response. After getting response it is setting that as value of TextArea

<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" 
         width="100%" height="100%" >
  <mx:Panel id="pnlMain" width="514" height="376" layout="absolute" 
  title="Serve Resource Example">
    <mx:Button label="Render request" y= "11" id="resourceUrl" 
    click="makeRenderCall()"  x="351"/>
    <mx:Button label="Process Action request" y= "54" id="resourceUrl0" 
    click="makeProcessActionCall()"  x="351"/>
    <mx:TextArea x="7" y="135" width="493" height="198"  id="displayText"/>
    <mx:TextInput x="142" y="10" id="httpMethod" text="GET"/>
    <mx:Label x="10" y="12" text="Http Method" width="124"/>
    <mx:Label x="10" y="54" text="Parameters"/>
    <mx:TextInput x="142" y="54" id="httpParam"/>
    <mx:Label x="10" y="106" text="Portlet Response"/>
  </mx:Panel>
  <mx:Script>
    <![CDATA[
      import flash.external.*;
      import mx.controls.Alert;
      import mx.rpc.events.FaultEvent;
      import mx.rpc.events.ResultEvent;
      import mx.rpc.http.HTTPService;
      //Event handler for handling button click 
      public function makeProcessActionCall():void
      {
        if (ExternalInterface.available) {
          var portletUrl:String = ExternalInterface.call("getProcessActionUrl");
          useHttpService(portletUrl);
        } else
          displayText.text = "Unable to call JavaScript";
      }
      public function makeRenderCall():void
      {
        if (ExternalInterface.available) {
          var portletUrl:String = ExternalInterface.call("getRenderUrl");
          useHttpService(portletUrl);
        } else
          displayText.text = "Unable to call JavaScript";
      }
      //This method is used for making a URL call
      private var service:HTTPService
      public function useHttpService(url:String):void {
        service = new HTTPService();
        service.url = url;
        service.resultFormat = HTTPService.RESULT_FORMAT_TEXT;
        service.method = httpMethod.text;
        service.addEventListener("result", httpResult);
        service.addEventListener("fault", httpFault);
        service.send(parameters);
      }
      //This callback gets called in case if the http response is returned
      public function httpResult(event:ResultEvent):void {
        var result:Object = event.result;
        displayText.text = event.result.toString();
      }
      //This call back gets called in case of error in http request
      public function httpFault(event:FaultEvent):void {
        var faultstring:String = event.fault.faultString;
        displayText.text = event.fault.faultDetail;
        Alert.show(faultstring + event.fault.faultDetail + event.fault.rootCause);
      }
    ]]>
  </mx:Script>
</mx:Application>