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What is a good use case for static import of methods?
I rarely ever see a static import in java like this:
import static java.lang.Math.*;
Then you could access PI without having to call Math.PI.
Since you don't see this that often, does that mean it is a bad design to do this?
I prefer not to use them, simply because I want to see where each constant is defined. If your classes and your constants are named appropriately, it helps readability a lot.
Then again, if you're using a lot of constants from the same class and it's obvious where they come from, you're better off with a wildcard import.
It is not bad design, but in my opinion Math.PI is clearer for maintaneinance than just PI.
Sometimes yes. When you use a static import, the fields and methods from the class you statically imported might "look like" they come from your class.
This does impact understandability, IMHO.
That said, I use it all the time in JUnit tests!
It's not bad. It's just usually not necessary. I personally use it whenever my program uses a lot of calls to java.lang.Math.
Most people also don't know about it since it's so infrequently used. Same thing goes to other constructs like static constructors.
Math was around before import static which is why most developers would tend to use the older form.
