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And: you can access non-public methods / variables from another class if they are in the same "package", as long as they aren't declared private. This is a Java idiom which isn't really represented in Greenfoot; all your classes are in the same package. But you can't call non-public methods from a class in a different package. For instance, there are some methods in the Actor class which are not public and which you can't call. (They're not listed in the API documentation - because you are not meant to be able to call them). Using 'static' works if there is only one object you are in

Thanks, Davin. I'll take a look at it!

ok

One of my students found it on the Scenario menu. Dick Baldwin

Thanks Wagnerf and DonaldDuck. I'm slowly re-learning Java :)

Aha - makes sense now thanks. Now to get the rest of the game to work.....

There's a full list here: http://www.java-tips.org/java-se-tips/java.lang/character-escape-codes-in-java.html \n, \\ and \" are the ones you'll most commonly use.

Thanks for the advice... I decided to use bourne's GUI and then modify it to act as two components that work as a team to identify a username/ password combo. Thanks!

Thank you all! I will test both of these out shortly and announce whether or not they work.

You're looking at Newton's law of universal gravitation if you want to do some reading around :-)

When you declare a field such as you had originally, you're essentially declaring a space that fits a particular type, in this case a list. You haven't actually put a list there yet, that comes when you do: <Code Omitted>That way you've created a new object and assigned it to listData, and you can manipulate it by calling methods (such as add.) When you don't create the object you're trying to manipulate an object that's not there, or "null" - hence NullPointerException. When you see an exception like that, that's almost always what will be going on!

If you still want more help with this then it'd help to be a bit more specific - what have you tried so far? Have you got any code that we can work from? Generally speaking, if you have a class you can implement the equals() method and subsequently call it to work out if two particular objects are equal, but how to implement it depends on the context!

im back