ArrayList list=new ArrayList();
Student student=new Student();
student.setAge(30);
student.setName("张三");
student.setAge(20);
student.setName("张三");
student.setAge(40);
student.setName("张三");
list.add(student);请问我在add时 或者读取list的时候怎么按照age去排序?
Student student=new Student();
student.setAge(30);
student.setName("张三");
student.setAge(20);
student.setName("张三");
student.setAge(40);
student.setName("张三");
list.add(student);请问我在add时 或者读取list的时候怎么按照age去排序?
{
public int compare(Student d1, Student d2)
{
return d1.getAge()-d2.getAge();
}
});
然后顶LS
是一个Collection的帮助类 ,里面有 集合的复制、排序等等通用方法,已经封装好的。
Student student=new Student();
student.setAge(30);
student.setnum(2);
student.setName("张三");
student.setAge(30);
student.setnum(1);
student.setName("李四");
student.setAge(40);
student.setName("王五");
student.setnum(3);
list.add(student);当有2个数需要排序时 怎么处理?