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2.21 Testing the Integer Swapping Code

Juppies 2 by Dr Heinz M. Kabutz

We run our game and see whether it works. Unfortunately an ArrayIndexOutOfBoundsException greets us when we try to play our game.

Our unit test passes, but when we look at the output we see that after shuffle, our indexes are [-1, -3, 19, -14, 10, 2, -25, 14, 19, 24]. Ooops. That's not really what we wanted to see. We definitely made a mistake in our code.

We now add more code to our test to ensure that the numbers in the array are the same as before our shuffle. We do this by sorting the array and again converting it to a String. The value of sorted should be the same as beforeShuffle.


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