ExtJS 2 and JSR 311 (Jersey)

For a side project at work, I've been working on new UI components using ExtJS and powering this front-end with a JSR 311 (Jersey) back-end.

The other day I was able to get something working for the first time that has troubled me for a bit: dynamic saving of an EditorGridPanel. Basically, the EditorGridPanel gives you inline editing of a table, and then I trigger a save of this data through a REST call back to the server.

The front-end:

function updateUser(e) {
var thisUrl = '/' + e.record.id;
var f = e.field;
var v = e.value;
var data = { 'field' : f, 'value' : v };
var p = Ext.util.JSON.encode(data);
Ext.Ajax.request({url: thisUrl, method: 'POST', params: p});
}

The back-end:

@HttpMethod("POST")
public void updateField(String body) throws JSONException, IllegalAccessException, InvocationTargetException, NoSuchMethodException {
JSONObject o = new JSONObject(body);
PropertyUtils.setSimpleProperty(user, o.getString("field"), o.get("value"));
RealmManager.instance().updateUser(user);
}

As might be obvious, this is to save some details about a user.

One thing I wasn't able to get working was the jsonData option for the Ajax.request call. Jersey would complain about media headers and what not that it couldn't convert into anything.