如何在Java中对同一包的类使用静态导入

Question

Within my project package "pypapo.alphabet" I would like to have one class "alphabetStatic" that contains all frequently used variables (paths, directories, files, constants, etc...) as static final fields throughout the project. In order to not fill up the code of the other classes with the "alphabetStatic"-prefix every time I access one of those static final fields I would like to perform some kind of "import static alphabetStatic". I know that the import static statement refers to the classes of a package. However is it possible to import the fields of a class in such manner?

Answer 1

Nothing prevents you from importing package X from inside package X.

So

import static status pypapo.alphabet.alphabetStatic.*;

should definitely work for you.

Answer 2

I know that the import static statement refers to the classes of a package.

Not really. It refers to static members of a class.
You can use import static with a fullquafiliedclassname.* (to mean any static member of the class) or with specific static field or method of a class.

For example to make an import static of a specific static field or method of a class, this is the syntax :

import static packages.Clazz.fieldOrMethod;

1) static field example

So you could do it to import the static out field form System :

import static java.lang.System.out;

and use it :

out("...");

1) static method example : same syntax.

import static org.junit.jupiter.api.Assertions.assertEquals*;

And use it :

assertEquals(expected, actual);

3) All static members of a class

Just suffix it with a wildcard :

import static org.junit.jupiter.api.Assertions.*;

Answer 3

Try this:

import static pypapo.alphabet.AlphabetStatic.*;

Note that classe names in Java must start with an uppercase letter.