sourceExecs += ((Operator)allSources.get(i)).numExecutions;
sourceExecs += ((Operator)allSources.get(i)).getPhaseExecutions();
    int getSourceExecs() {        int sourceExecs = 0;        // can't use iterator here for performance reasons -- it is        // the inner loop when the sinks are filewriters        for (int i=0; i<allSources.size(); i++) {            sourceExecs += ((Operator)allSources.get(i)).numExecutions;        }        return sourceExecs;    }