// let all single capital letters of alphabet (except A) be classes that extends abstract class A

A obj = myFunction();
if(A.getClass.equals(X.class)){
    ((X)obj).doX();
}else if(A.getClass.equals(Y.class)){
    ((Y)obj).doY();
}else if(A.getClass.equals(Z.class)){
    ((Z)obj).doZ();
}else if(A.getClass.equals(W.class)){
    ((W)obj).doW();
}else if(A.getClass.equals(R.class)){
    ((R)obj).doR();
}else if(A.getClass.equals(G.class)){
    ((G)obj).doG();
}else if(A.getClass.equals(Q.class)){
    ((Q)obj).doQ();
}else if(A.getClass.equals(F.class)){
    ((F)obj).doF();
}else if(A.getClass.equals(D.class)){
    ((D)obj).doD();
}else if(A.getClass.equals(N.class)){
    ((N)obj).doN();
}
// (...)
// AND IT'S GOING FOR 100 LINES FOR FUCKS SAKE