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

public class Example {
    private static final String PATH = "ok";

    private static void changePath() throws Exception {
        Field field = Example.class.getDeclaredField("PATH");
        field.setAccessible(true);

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

        field.set(null, "new value");
    }

    public static void main(String[] args) throws Exception {
        changePath();
        System.out.println(PATH); // still prints ok
    }
}