import org.checkerframework.checker.guieffect.qual.*;

public class Specialization {

    @PolyUIType
    public static interface I {
        @PolyUIEffect
        public void m();
    }

    public static void reqSafe(@AlwaysSafe I i) {}

    @UIEffect
    public static void reqUI(@UI I i) {}

    @PolyUIType
    public static interface Doer {

        public void doStuff(@PolyUI Doer this, @PolyUI I i);
    }

    @AlwaysSafe public static class SafeDoer implements @AlwaysSafe Doer {
        // :: error: (override.param.invalid)
        public void doStuff(@AlwaysSafe SafeDoer this, @AlwaysSafe I i) {}
    }

    public void q(@AlwaysSafe Doer doer, @UI I i) {
        doer.doStuff(i);
    }

    public static void main(String[] args) {

        @AlwaysSafe Doer d =
                new @AlwaysSafe Doer() {
                    @SafeEffect
                    // :: error: (override.param.invalid)
                    public void doStuff(@AlwaysSafe I i) {
                        reqSafe(i);
                    }
                };
        @UI I ui =
                new @UI I() {
                    public void m() {
                        reqUI(null);
                    }
                };
        Specialization q = new Specialization();
        q.q(d, ui);
    }
}