I created a class that implements java.util.Map<String, Object>. Then I created a variable of type java.util.Map<String, Object> and used the delegate method wizard to wrap all the methods, which generated methods like:

    public Object remove(Object key){
        return actualMap.remove(key);
    }

This generates a Suspicious method call warning, "Expected type String but found Object".  It seems to me the hint should offer a fix that converts the Object to a String.