Question

I want to write perfect Java code, so please let me ask this question.

I want to use a never-changing String variable in my method like this:

1. String STR4SEARCH_START = "Abc";

And I could define it just in my method, and because it doesn’t need to change, I could also define it in my class like this:

2. private final String STR4SEARCH_START = "Abc";
3. private static final String STR4SEARCH_START = "Abc";
4. public final String STR4SEARCH_START = "Abc";
5. public static final String STR4SEARCH_START = "Abc";

Here is my question: from way1-way5, which one is the best, and could you please explain why?

Thank you very much.

Answer 1

It depends. If you want others (outside of your class) to be able to view it, then use public not private, and vice versa. Other than that, I would certainly use static final because you essentially want to define an unchanging constant, as you said. static because each instantiation of your class will not require a different value, and final because its value will not change.