Right now I m trying to understand how Flex works with Java (Flex -> BlazeDS -> Java). I tried to follow THIS tutorial and everything works fine, I just don t understand why do we need to call java function this way:

<mx:Script>
    <![CDATA[
        import mx.rpc.events.FaultEvent;
        import mx.rpc.events.ResultEvent;

        // Send the message in response to a Button click.
        private function echo():void {
            var text:String = ti.text;
            remoteObject.echo(text);
        }

        // Handle the recevied message.
        private function resultHandler(event:ResultEvent):void {
            ta.text += "Server responded: "+ event.result + "
";
        }

        // Handle a message fault.
        private function faultHandler(event:FaultEvent):void {
            ta.text += "Received fault: " + event.fault + "
";
        }
    ]]>
</mx:Script>

为什么我们需要使用Event/ResultEvent来调用Java函数？为什么不能像这样做：

EchoService.echo("hi")

谢谢 (xiè xiè)