Using Spock to mock private static final variables in Java

Question

I\'m trying to write some Spock tests with Groovy to test some Java code (specifically a servlet Filter). I have some private static and private static fi

Answer 1

Based on what I learned from https://stackoverflow.com/a/25031713/239408, this works for me in spock

import java.lang.reflect.Field
import java.lang.reflect.Modifier

...

    def setup() {

        Field field = BackendCredentials.getDeclaredField("logger")
        field.setAccessible(true);

        Field modifiersField = Field.class.getDeclaredField("modifiers");
        modifiersField.setAccessible(true);
        modifiersField.setInt(field, field.getModifiers() & ~Modifier.FINAL);

        field.set(null, Mock(Logger))
    }

Looks like you are missing the unsetting of the Modifier.FINAL flag.

Answer 2

Either you need to use PowerMock (or another similar solution), or refactor your code. Spock does not support mocking of private/static/final methods on its own. This limitation is also present in Mockito, so that must give you a hint on best-practices.