Question

New to java. Unclear about this piece of code:

ParseQuery query = new ParseQuery("GameScore");
query.getInBackground("xWMyZ4YEGZ", new GetCallback() {
  public void done(ParseObject object, ParseException e) {
    if (e == null) {
      // object will be your game score
    } else {
      // something went wrong
    }
  }
});

With new GetCallback() {....}, is it instancing an instance of GetCallback class or defining a subclass of Getcallback class or both?

Is this Java’s way of doing anonymous functions in C/Objective-C and Ruby’s blocks?

Answer 1

It’s doing both. It’s declaring an anonymous inner class (you’ll see a corresponding .class file in the compiled output) and creating a new instance of it.

Java doesn’t have a way of creating just an anonymous function (as of Java 7) – this is as close as it gets though.