Builder pattern subclassing - solved, with traits?

class Base<SUB extends VariantA<SUB> & VariantB<SUB>> implements VariantA<SUB>, VariantB<SUB> {

    public Base build() {
        System.out.println("Building in Base class");
        return this;
    }
}

interface VariantA<SELF extends VariantA<SELF>> {

    default SELF withVariantAParam(String param) {
        System.out.println("Here in Variant A class with " + param);
        return (SELF) this;
    }

}

interface VariantB<SELF extends VariantB<SELF>> {

    default SELF withVariantBParam(String param) {
        System.out.println("Here in Variant B class with " + param);
        return (SELF) this;
    }

}

class Subclass extends Base<Subclass> {

    public Subclass withSubclassParam(String param) {
        System.out.println("Here in Subclass with " + param);
        return this;
    }
}

class AnotherSubclass extends Base<AnotherSubclass> {

    public AnotherSubclass withAnotherSubclassParam(String param) {
        System.out.println("Here in AnotherSubclass with " + param);
        return this;
    }
}

public class Client {
    public static void main(String[] args) {

        System.out.println("Subclass example:\n");
        new Subclass()
                .withSubclassParam("s1")
                .withVariantAParam("foo")
                .withSubclassParam("s2")
                .withVariantBParam("bar")
                .withSubclassParam("s3")
                .build();


        System.out.println("\n\nAnotherSubclass example:\n");
        new AnotherSubclass()
                .withAnotherSubclassParam("s1")
                .withVariantAParam("foo")
                .withAnotherSubclassParam("s2")
                .withVariantBParam("bar")
                .withAnotherSubclassParam("s3")
                .build();
    }
}