Question

Possible Duplicate:
Why is using a wild card with a Java import statement bad?
Performance difference between a wild card import and the required class import

What are the implications of importing a java package using .* versus specifying a package explicitly. For example,

import java.lang.annotation.Annotation;

instead of

import java.lang.annotation.*;

Are there penalties at compile time or run time when using wild card?

Answer 1

Absolutely no effect on run time.

Wildcard imports are probably marginally slower at compile-time, but I wouldn’t think you’d need to care.