hashmap ArrayList
来源:百度知道 编辑:UC知道 时间:2024/06/09 02:48:52
设置的方法:
//查询出来的所有学生
List<Student> allStudents = null ;
Map<String,List<Student>> map = new HashMap<String, List<Student>>();
for(Student student : allStudents)
{
if(map.containsKey(student.getGroupNo()))
{
List<Student> students = map.get(student.getGroupNo());
students.add(student);
}
else
{
List<Student> students = new ArrayList<Student>();
students.add(student);
map.put(student.getGroupNo(), students);
}
}
Student类:
public class Student
{
private String groupNo;
private String name;
public String getGroupNo()
{
return groupNo;
}
public void setGroupNo(String groupNo)
{
this.groupNo = groupNo;
}
public String getName()
{
return name;
}
public void setName(String name)