Web App Solution Blog

I recently needed to send a Java byte[] to Flex that ultimately needed to be converted to an ActionScript String on the Flex side. I wrestled with it for a bit before I realized that I needed to make the byte[] on the Java side encoded with UTF-8.

Here’s a quick EchoService I created in Java that takes a String parameter from Flex, converts it into a byte[], and then sends it back to Flex, as well as the accompanying Flex code that handles the service’s result and transforms the byte[] back into a String in ActionScript.

package com.wasi.services.test;

import java.io.UnsupportedEncodingException;

public class EchoService
{
	public String echo(String param)
	{
		return param;
	}

	public int echo(int param)
	{
		return param;
	}

	public byte[] echoStringToByte(String param)
	{
		System.out.println("echoStringToByte: " + param);

		byte[] byteArray = null;

		try
		{
			byteArray = param.getBytes("UTF-8");
		}
		catch (UnsupportedEncodingException e)
		{
			e.printStackTrace();
		}
		return byteArray;
	}

}

And on the Flex side:

import mx.rpc.remoting.mxml.RemoteObject;
import mx.rpc.events.FaultEvent;
import mx.rpc.events.ResultEvent;

private var echoStringToByteService:RemoteObject;

private function init():void
{
	trace("init");

	this.echoStringToByteService = new RemoteObject();
	this.echoStringToByteService.destination = "echoService";
	this.echoStringToByteService.endpoint = "http://localhost:8080/bds/messagebroker/amf";
	this.echoStringToByteService.showBusyCursor = true;
	this.echoStringToByteService.addEventListener(ResultEvent.RESULT, onEchoStringToByteServiceResult);
	this.echoStringToByteService.addEventListener(FaultEvent.FAULT, onEchoStringToByteServiceFault);
}

private function onEchoServiceSubmit(evt:MouseEvent):void
{
	trace("onEchoServiceSubmit");

	var str:String;

	str = this.echoStringTextInput.text;
	this.echoStringToByteService.echoStringToByte(str);
}

private function onEchoStringToByteServiceResult(evt:ResultEvent):void
{
	trace("onEchoStringToByteServiceResult");

	var byteArray:ByteArray;

	byteArray = evt.result as ByteArray;

	// both the readUTFBytes() and toString() methods give return you the string
	trace("onEchoStringToByteServiceResult readUTFBytes = " + byteArray.readUTFBytes(byteArray.bytesAvailable));
	trace("onEchoStringToByteServiceResult toString = " + byteArray.toString());

	this.echoServiceResultText.text = byteArray.readUTFBytes(byteArray.bytesAvailable);
}

private function onEchoStringToByteServiceFault(evt:FaultEvent):void
{
	trace("onEchoStringToByteServiceFault");
}

In order to run this you’ll need to:

• Copy and paste the ActionScript listed above into a Flex Application tat calls the init() method on creationComplete.
• Have BlazeDS or LCDS running on a server (as you can see in the definition of my RemoteObject in Flex I created a small Java web-app with a context root of /bds).
• Configure remoting-config.xml by adding in the following destination node listed below.

<destination id="echoService">
	<properties>
		<source>com.wasi.services.test.EchoService</source>
		<scope>application</scope>
	</properties>
</destination>

NOTE: I removed a couple things for clarity and this code has not been retested to verify that it still runs, but you should get the idea.

Tweet This Post