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No, you can directly reference the enum constants, no need for any other values.

You'll need to store the current state of the cell in a variable. The syntax for that would be something like this:...

Basically, instead of having a boolean value, you'd have something like a CellState value (whatever you want to call your enumeration type). That type would have three different enum constants:...

After a quick search of "java enum" (to be blatantly honest, I even misspelled it as "java enu"), these two tutorials are listed. They're pretty good.

Enums
Enum Types (The Java™ Tutorials >...

You might want to look into using an enum instead of a boolean. That way you can easily check against three different conditions.