Question

(function() {
function alertJSON(json) {
    alert("json:" + json);
}
function treeInit() {
    buildJSONTree(alertJSON);
}
function buildJSONTree(callback) {
    var handleSuccess = function(o) {
        var json = YAHOO.lang.JSON.parse(o.responseText);
        callback(json);
    };
    var handleFailure = function(o) {
        alert("FAILURE");
    };
    var asyncCallback = {
        success : handleSuccess,
        failure : handleFailure,
        timeout : 5000
    };
    var send = function(o) {
        var sUrl = "http://127.0.0.1:8080/TestMVC/resources/json/category-subject.json";
        YAHOO.util.Connect.asyncRequest('GET', sUrl, asyncCallback);
    }();
}
YAHOO.util.Event.onDOMReady(treeInit);
})();

And then in my html file I include that script and it executes. I can follow it in the debugger until it executes the asyncRequest, it just returns and neither of my handlers executes.

Answer 1

I made a fiddle and for me it is working. The success callback is called if the resource is available.

http://jsfiddle.net/uZfX5/

In the fiddle the server returns no json and so the json parser crashes but i think that was not the point.