Sign Up to our social questions and Answers Engine to ask questions, answer people’s questions, and connect with other people.
Login to our social questions & Answers Engine to ask questions answer people’s questions & connect with other people.
Lost your password? Please enter your email address. You will receive a link and will create a new password via email.
Please briefly explain why you feel this question should be reported.
Please briefly explain why you feel this answer should be reported.
Please briefly explain why you feel this user should be reported.
Does the placing of default statement affect efficiency in Java? Is there difference between:
switch (a) {
case 0: return 0;
case 1: default: return -1;
case 2: return 2
...
case 99: return 99;
}
vs
switch (a) {
case 0: return 0;
case 1: return -1;
case 2: return 2;
...
case 99: return 99;
default: return -1;
}
Even in the most naive implementation this cannot produce a difference in performance, but with Java you are so far removed from the actual machine code this will turn into that you should definitely never even attempt to optimize this or any other similar piece of code. In fact, even if you wrote the dumbest cascade of
else-ifs, you’d still stand a solid chance of JIT turning that into a superfast hash-lookup-based machine code.