How to enforce static imports for some methods using checkstyle?

Question

How to enforce static imports for some methods using checkstyle?

For example

I want the following method to be used only from static import:

import static java.util.Objects.isNull;
import static java.util.Objects.nonNull;

So code like this shouldn't be allowed:

if (Objects.nonNull(varName)) {

Any ideas how to achieve that with (preferably) standard or non standard tools?

Answer 1

You could forbid the String that imports Objects:

<module name="RegexpSinglelineJava">
    <!-- Please statically import methods -->
    <property name="format" value="import java.util.Objects;"/>
</module>