选用哪个集合更为好一点 - 黑马程序员技术交流社区

import java.util.*;
/*
把学生分装成对象，存储到map集合当中
*/
class Student
{
private String name;
private String id;
Student(String name,String id)
{
this.name = name;
this.id = id;
}
public String toString()
{
return name+";;;"+id;
}
}
class Demo4
{
public static void main(String[] args)
{
TreeMap<String,List<Student>> tr = new TreeMap<String,List<Student>>();//这里可不可以使用Set集合？
List<Student> yure = new ArrayList<Student>(); //两种方式哪个更好一点呢？
List<Student> jiuye = new ArrayList<Student>();
tr.put("yurenban",yure);
tr.put("jiuyeban",jiuye);
jiuye.add(new Student("zhangsan1","01"));
jiuye.add(new Student("zhangsan2","02"));
yure.add(new Student("lishi1","03"));
yure.add(new Student("lishi2","04"));
//Set<String> set= tr.keySet();
Iterator<String> it = tr.keySet().iterator();
while(it.hasNext())
{
String s = it.next();
List<Student> l = tr.get(s);
getRome(l);
}
}
public static void getRome(List<Student> list)
{
Iterator<Student> it = list.iterator();
while(it.hasNext())
{
Student stu = it.next();
System.out.println(stu);
}
}
}

复制代码