树深度优先遍历实例

public Set<Integer> getOrganizationRangeIdSet(int rootId) {
    Set<Integer> resultSet = new HashSet<>();
    resultSet.add(rootId);

    OrganizationMapper organizationMapper = getBaseMapper();
    Set<Integer> childrenOrganizationIdSet = organizationMapper.getChildrenOrganizationIdSet(rootId);
    for(Integer id : childrenOrganizationIdSet) {
        resultSet.addAll(getOrganizationRangeIdSet(id));
    }
    return resultSet;
}