我想随机选择一个学生messfood()
。试图在那里打印学生名字。每周,应该选择任何学生作为乱七八糟的食物费用。试用String random = list.get(new Random().nextInt(list.size()));
。但是显示错误。帮我解决这个问题。从数组列表中随机选择
public class Student {
int rollNo, yearOfStudy;
String fName, lName, activity;
Student(int rollNo, String fName, String lName, int yearOfStudy) {
this.rollNo = rollNo;
this.fName = fName;
this.lName = lName;
this.yearOfStudy = yearOfStudy;
}
public void display(){
System.out.println("Roll Number: "+rollNo +"\nName: "+fName+ " "+lName + "\nYear Of Study: "+yearOfStudy+"\n\n");
}
public void messFood(){
System.out.println("week 1, Mess food Incharge: ");
}
}
class Collection {
public static void main(String[] args) {
Student s1 = new Student(1, "Alex", "Iwobi", 2013);
Student s2 = new Student(2, "Denis", "Suarez", 2013);
Student s3 = new Student(3, "Gerard", "Deulofeu", 2013);
Student s4 = new Student(4, "Petr", "Cech", 2013);
List studentList = new ArrayList();
studentList.add(s1);
studentList.add(s2);
studentList.add(s3);
studentList.add(s4);
Iterator it = studentList.iterator();
while(it.hasNext()){
Student s=(Student)it.next();
s.display();
}
}
}
您正在使用原始集合并期望'String'而不是'Student'。 – Mena
什么是错误? –
当然,阅读错误消息可能会有所帮助。 – Gassa