Is it bad practice for a class to have only static fields and methods?

Question

I have a class that consists only of static member variables and static methods. Essentially, it is serving as a general-purpose utility class.

Is i

Answer 1

Note also that Java specifically introduced the static import: (http://en.wikipedia.org/wiki/Static_import)

Static import is a feature introduced in the Java programming language that members (fields and methods) defined in a class as public static to be used in Java code without specifying the class in which the field is defined. This feature was introduced into the language in version 5.0.

The feature provides a typesafe mechanism to include constants into code without having to reference the class that originally defined the field. It also helps to deprecate the practice of creating a constant interface: an interface that only defines constants then writing a class implementing that interface, which is considered an inappropriate use of interfaces[1].

The mechanism can be used to reference individual members of a class:

 import static java.lang.Math.PI;
 import static java.lang.Math.pow;

or all the static members of a class:

 import static java.lang.Math.*;

Answer 2

No, I don't think so at all. It is worse practice to have a class full of instance methods which don't actually depend on a particular instance. Making them static tells the user exactly how they are intended to be used. Additionally, you avoid unnecessary instantiations this way.

EDIT: As an afterthought, in general I think its nice to avoid using language features "just because", or because you think that that is the "Java way to do it". I recall my first job where I had a class full of static utility methods and one of the senior programmers told me that I wasn't fully harnessing the OO power of Java by making all of my methods "global". She was not on the team 6 months later.