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Java Java Objects (Retired) Delivering the MVP Determining if It Is Solved

tomtrnka
tomtrnka
9,780 Points
Posted by tomtrnka
tomtrnka
9,780 Points

method isSolved() --- usage of .contains() instead of .indexOf()

Craig used the static method "indexOf()" to determine whether the answer is solved.

I always try to write the code before Craig does and then I compare the differences. In this case I can't really say if I'm right or not, cause this block of code works for me fine as well:

My code: public boolean isSolved() { return !getCurrentProgress().contains("-"); }

Craig's code: public boolean isSolved() { return !getCurrentProgress().indexOf('-') == -1 ; }

Can someone explain why should we use .indexOf() instead of .contains()?

Thanks

1 Answer

markmneimneh
markmneimneh
14,132 Points

It is a matter of taste a preferences.

My code: public boolean isSolved() { return !getCurrentProgress().contains("-"); } here you are saying does whatever comes back from getCurrentProgress(). contains the character '-'. The answere will be true ot false and then you take action based on the boolean value.

Craig's code: public boolean isSolved() { return !getCurrentProgress().indexOf('-') == -1 ; } Here Craigs is asking ... does whatever string getCurrentProgress returns ... I am going to test if the character '-' is in the string ... recall ,,, string can be thought of as an array of chars ... so now MyString.indexOf('-') == -1 will return a boolean (T/F) ... which is essentially same thing as you had.

Again, which one is better ? It is a matter of taste a preferences. Hope this helps. If this answers your question, please mark the question as answered.