Flex and Java - HTTP Get Example

Below is Flex code sample to communicate to a Java servlet in the back-end using HTTP Service.

<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute">
  <mx:Script>
   <![CDATA[
    import mx.rpc.events.ResultEvent;
    import mx.rpc.events.FaultEvent;
    import mx.controls.Alert;

    [Bindable]
    private var xmldata:XML;

   private function send_data():void {
         httpXmlDataService.send();
    }

   private function faultHandler(event:FaultEvent):void{
         mx.controls.Alert.show(event.fault.message,"Error in getting result");
    }
   private function resultHandler(event:ResultEvent):void{
        xmldata=event.result as XML;
   }
   private function displayBeforeTax(row:Object,column:DataGridColumn):String{
        return row.profit.beforetax;
   }
   private function displayAfterTax(row:Object,column:DataGridColumn):String{
        return row.profit.aftertax;
   }
   ]]>
 </mx:Script>

<mx:HTTPService  id="httpXmlDataService"
        url="http://localhost:8080/flexJavaIntegration/opendesk"
        resultFormat="e4x"
        result="resultHandler(event)"
        fault="faultHandler(event)"
        useProxy="false"/>

            
 <mx:Panel x="43" y="10" width="588" height="369" layout="absolute">
   <mx:DataGrid x="50" y="23" width="469" height="265" dataProvider="{xmldata.item}">
    <mx:columns>
      <mx:DataGridColumn headerText="Type" dataField="@type"/>
      <mx:DataGridColumn headerText="Sales" dataField="sales"/>
   
      <mx:DataGridColumn headerText="Profit before tax" labelFunction="displayBeforeTax"/>
      <mx:DataGridColumn headerText="Profit after tax" labelFunction="displayAfterTax"/>
     </mx:columns>
   </mx:DataGrid>
   
   <mx:Button x="66" y="296" label="Get Data" click="send_data()" />
 </mx:Panel>
</mx:Application>
 

Now, here is the Java Servlet.

package com.opendesk.flexjava;

import java.io.IOException;
import java.io.PrintWriter;
import java.util.Enumeration;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class OpenDeskService extends HttpServlet {

 public void doPost(HttpServletRequest req, HttpServletResponse res)
   throws ServletException, IOException {  
  
  Enumeration  en = req.getParameterNames();

  while (en.hasMoreElements()) {
   String key = (String) en.nextElement();
   String value = (String) req.getParameter(key);

   System.out.println("Key : " + key + " Value : " + value);
  }
 }

 public void doGet(HttpServletRequest request, HttpServletResponse response)
   throws IOException, ServletException {
  
  response.setContentType("text/xml");
  PrintWriter writer = response.getWriter();

  writer.println("<?xml version=\"1.0\"?>\n");
  writer.println("<salesdata>");
  writer.println("<item type=\"xxxxxxxxxxxxCDs\">");
  writer.println("<profit>");
  writer.println("  <beforetax>1750</beforetax>");
  writer.println("  <aftertax>1600</aftertax>");
  writer.println("</profit>");
  writer.println("<sales>21000.23</sales>");
  writer.println("</item>");
  writer.println("<item type=\"DVD\">");
  writer.println("<profit>");
  writer.println("  <beforetax>1550.34</beforetax>");
  writer.println("  <aftertax>1350.10</aftertax>");
  writer.println("</profit>");
  writer.println("<sales>11010.98</sales>");
  writer.println("</item>");
  writer.println("</salesdata>");
 }
}