private void addToParticipants(final Participant participant) {
// check for no-op
if (participant == null || getParticipants().contains(participant)) {
return;
}
// dissociate arg from its current parent (if any).
participant.getActivities().remove(this);
// associate arg
participant.getActivities().add(this);
getParticipants().add(participant);
// additional business logic
// onAddToParticipants(participant);
}
private void removeFromParticipants(final Participant participant) {
// check for no-op
if (participant == null || !getParticipants().contains(participant)) {
return;
}
// dissociate arg
participant.getActivities().remove(this);
getParticipants().remove(participant);
// additional business logic
// onRemoveFromParticipants(partipipant);
}