public class GroupBy {
public static void main(String[] args) {
List data= new ArrayList();
Map map = new HashMap();
map.put("hostDepartmentName", "综合部");
map.put("contractCode", "K
public class test {
public static void main(String[] args) {
List list = new ArrayList();
Bill b = new Bill();
b.setType("A");
b.setMoney(1);
list.add(b);
b = new Bill();
b.setType("B");
