我有一个集合 ArryList集合中存放一些类,这些类的种类有为“1”的有为“2”的,请问该集合有多少种类,每个种类中有多少个?代码如下:
ArrayList<Order> orders = new ArrayList<Order>();
// TODO Auto-generated method stub
Order order1 = new Order();
Order order2 = new Order();
Order order3 = new Order();
Order order4 = new Order();
order1.setTittle("tittle1111");
order2.setTittle("tittle2222");
order3.setTittle("tittle3333");
order1.setText("text1111");
order2.setText("text2222");
order3.setText("text3333");
order4.setTittle("tittle1111");
order4.setText("text4444");
orders.add(order1);
orders.add(order2);
orders.add(order3);
orders.add(order4);各位试试啊,看着简单,做起来就难了我没弄出来,,,求指点
ArrayList<Order> orders = new ArrayList<Order>();
// TODO Auto-generated method stub
Order order1 = new Order();
Order order2 = new Order();
Order order3 = new Order();
Order order4 = new Order();
order1.setTittle("tittle1111");
order2.setTittle("tittle2222");
order3.setTittle("tittle3333");
order1.setText("text1111");
order2.setText("text2222");
order3.setText("text3333");
order4.setTittle("tittle1111");
order4.setText("text4444");
orders.add(order1);
orders.add(order2);
orders.add(order3);
orders.add(order4);各位试试啊,看着简单,做起来就难了我没弄出来,,,求指点
orders.add(new String());
orders.add(new Date());
orders.add(new Xxx());
//以此类推 楼主是不是想表达哦这个问题呢?