Calling multiple methods from one RemoteObject in Flex and Actionscript using BlazeDS

Nick — Wed, 19 Aug 2009 20:22:36 +0000

BlazeDS allows us to use RPC to access our Java objects from an Adobe Flex or AIR app. This is a simple example that allows you to have a remote java object which you will make calls upon from Flex (or Actionscript). There are plenty of BlazeDS remoting tutorials out there. This HOW-TO shows how to create an actionscript class to handle your remote objects and handlers as well as linking more than one method to a single remote object.

This HOW-TO assumes you have the knowledge to create a small flex app and a server-side java project using BlazeDS. If you don’t know how to do this, there are tons of tutorials out there like this one.

Here’s the java object that we’ll be calling methods on from Flex:

public class MyRemoteService {
	public MyRemoteService() { }
 
	public String getSessionId() {
		String sessionId = FlexContext.getFlexSession().getId();
		System.out.println("returning sessionId "+sessionId);
		return sessionId;
	}
 
	public String[] getMyData() {
		return stuff from database or whatever
	}
}

Our RemoteObject will be called remoteService and will call the two methods getSessionId() and getMyData(). The following is the mxml for remoteService that has the two methods. Each method has a name attribute and attributes to set handlers for a fault and result.

This next code block does the same thing as our above code, except it’s an actionscript class. It handles the same two methods.

public class ConnectionManager
{
	import mx.controls.Alert;
	import mx.rpc.events.FaultEvent; 
	import mx.rpc.AsyncToken;
	import mx.rpc.Responder;
	import mx.rpc.events.ResultEvent;
	import mx.rpc.remoting.mxml.RemoteObject;
	import mx.messaging.Channel; 
	import mx.messaging.ChannelSet; 
	import mx.messaging.channels.AMFChannel;  
 
	private var blazeUrl:String = "http://localhost:8080/BlazeServer/messagebroker/";
	private var remoteService:RemoteObject = new RemoteObject;
 
	public function ConnectionManager()
	{
		var cs:ChannelSet = new ChannelSet(); 
		var myAMF:Channel = new AMFChannel("my-amf", blazeUrl + "amf"); 
		cs.addChannel(myAMF); 
		remoteService.channelSet = cs; 
 
		remoteService.destination = "remoteServiceDestination";
		remoteService.showBusyCursor = true;
		var rpcCall:AsyncToken;
 
		rpcCall = remoteService.getSessionId();
		rpcCall.addResponder(new Responder(handler_getSessionIdSuccess, handler_getSessionIdFault) );
 
		rpcCall = remoteService.getMyData();
		rpcCall.addResponder(new Responder(handler_getMyDataSuccess, handler_getMyDataFault) );
	}
 
	private function handler_getSessionIdSuccess(event:ResultEvent):void {
		trace(event);
		Alert.show("sessionId: "+event.message.body.toString(), "handler_getSessionIdSuccess");
	}
 
	private function handler_getSessionIdFault(fault:FaultEvent):void {
		trace(fault);
		Alert.show(fault.toString(), "handler_getSessionIdFault");
	}
 
	private function handler_getMyDataSuccess(event:ResultEvent):void {
		trace(event);
		Alert.show(event.message.body.toString(), "handler_getMyDataSuccess");
	}
 
	private function handler_getMyDataFault(fault:FaultEvent):void {
		trace(fault);
		Alert.show(fault.toString(), "handler_getMyDataFault");
	}
}

For a good book about Flex check out Flex 3 in Action

Quick Tomcat https SSL Config

Nick — Tue, 10 Mar 2009 19:04:52 +0000

Setting up your webapp to work with https and SSL encryption when using Tomcat is easier than most people think. Here’s a very quick HOW-TO to get you up and running…

The first thing you need to do is create a certificate. If you’re unfamiliar with certificates or SSL you can look at some of the following links to help school you:
http://tldp.org/HOWTO/SSL-Certificates-HOWTO/x64.html
http://www.ourshop.org/resources/ssl.html
http://www.wisegeek.com/what-is-the-difference-between-http-and-https.htm

Creating your certificate

Go to your JRE bin folder and there will be a file called “keytool”.
Type keytool -genkey -alias tomcat -keyalg RSA -keystore c:/.keystore The “keystore” parameter is optional. It’s the location where the certificate keystore will be stored. By default it will be stored in the current user’s home directory.
Upon executing, you will be prompted with a number of questions like name, location, organization, etc. For name I recommend using the domain or if need be the machine name.

Modifying the server.xml file

Locate the server.xml in $CATALINA_HOME/conf/server.xml
Open it and look for a section dealing with the SSL Connector. The section will look something like this:

<-- Define a SSL Coyote HTTP/1.1 Connector on port 8443 -->

Uncomment the block, and add in another attribute for the keystore location. We’ll add in keystoreFile=”c:\.keystore”, so when finished we’ll have:

<-- Define a SSL Coyote HTTP/1.1 Connector on port 8443 -->
 
           port="8443" minProcessors="5" maxProcessors="75"
           enableLookups="true" disableUploadTimeout="true"
           acceptCount="100" debug="0" scheme="https" secure="true";
           clientAuth="false" sslProtocol="TLS" keystoreFile="c:\.keystore">
>

For full workings of server.xml refer to the apache site.

Last step is to restart Tomcat and point the browser to:
https://localhost:8443
Remember the https and it uses port 8443 by default which can be changed in the server.xml

/home/nick » web-dev

Calling multiple methods from one RemoteObject in Flex and Actionscript using BlazeDS

Quick Tomcat https SSL Config