This solution uses an Asynchronous call. It will likely work better than a synchronous solution.
var request = new XMLHttpRequest();
request.open("GET", "../../data/file.json", false);
request.send(null);
request.onreadystatechange = function() {
if ( request.readyState === 4 && request.status === 200 ) {
var my_JSON_object = JSON.parse(request.responseText);
console.log(my_JSON_object);
}
}