Java

Excellent kata, enjoyed it very much.
However, I believe that there is an extra whitespace in line 3 of the first "corner" example (shown with a *):

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*\-----

instead of

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\-----

If this is intended to be a beginner-level kata, perhaps the instructions/requirements could be more explicit about the constructor (order of params?) and getters/setters (method names?). New programmers may not have learned the conventions for getting and setting.