public ContactIterator(Contact contact) {
if (contact.isLeaf()) {
nextLeaf = contact;
} else {
unfinishedIterators.push(contact.children());
}
}
private Contact findNextLeaf() {
while (true) {
if (unfinishedIterators.isEmpty()) {
return null;
}
Iterator<Contact> iterator = unfinishedIterators.pop();
if (iterator.hasNext()) {
Contact contact = iterator.next();
currentIterator = iterator;
if (iterator.hasNext()) {
unfinishedIterators.push(iterator);
}
if (contact.isLeaf()) {
return contact;
} else {
unfinishedIterators.push(contact.children());
}
}
}
}
