debug.html

<html>
<head>
<script>
function connect() {
	var field = document.getElementById('portText');
	var url = "http://www.eclipse.org/swt/frames.html";//"localhost:" + field.value + "/json";
	var xhr = XMLHttpRequest ? new XMLHttpRequest() : new ActiveXObject("Microsoft.XMLHTTP"); 
	if (xhr) {
alert(url);
		xhr.onreadystatechange=function() {
			if (xhr.readyState == 4) {
				alert(xhr.readyState + ":" + xhr.responseText);
			}
		}
		xhr.onerror = function() { 
			alert("onerror: " + xhr.status); 
		};
		xhr.open("GET", url, true);
		xhr.send(null)
	}
}

</script>
</head>
<body>

<textarea id="portText" rows="1" cols="99">
</textarea>
<input type=button id="connectButton" value="Connect" onClick="connect()">
<textarea id="console" rows="9" cols="99">
</textarea>
<input type=button id="evaluateButton" value="Evaluate" disabled="disabled" onClick="evaluate()">

</body>
</html>