Welcome to the Ranch
Beware of multiple constructors. I think every class should have a constructor, (even a
private constructor, which can be very useful for reasons explained
here), but multiple constructors give you multiple opportunities for something to go wring, I am afraid. Your two‑argument constructor, for example, doesn't initialise the
Array field (which should be called
array). So any use of that field won't work. It will be
null and you will have
this sort of exception thrown.
Only call your methods
getXXX() if they return something. I am afraid I can see another problem with that method. You correct the problems with the constructors and they run correctly, but there is another enhancement you should make which I am keeping quiet about at the moment. Now there is no way to guarantee that the method to fill the matrix is ever called. I suggest you call that method from the constructor. Beware: methods called from the constructor should be marked
private or
final. There is no need to use both modifiers.
Your printf call in line 35 won't work, I am afraid. Get rid of the +, and I suggest you change the numbers after % too.
System.out.printf("%6.2f, ", array[i][j]); will give you 8 characters per number, like this
-12.34, .
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