A subscription pattern S = ((C1, ..., Cn),F) is characterized by a set of n basic conditions, which are all evaluated for a given message m, and a n-ary function F(b1: bool, ..., bn: bool): bool, which is evaluated for the results of these conditions: S(m) = F(C1(m), ..., Cn(m)). A pattern is thus evaluated like a condition: S(o: obj): bool, and is represented in JAVA by an object of type Condition. The model diverges here from the concrete realization, in that the function F does not appear as such.