在for循环里使用nextline会报错Exception in thread 使用next就不会，是什么原因，求大佬

package demo2;
import java.util.ArrayList;
import java.util.Scanner;
public class Test{
public static void main(String[] args) {
Scanner in=new Scanner(System.in);
ArrayListas=new ArrayList<>();
for(int i=0;i<3;i++) {
String name=in.nextLine();
Student s=new Student(name);
while(true) {
String course=in.next();
if(course.equals("#")) {break;}
int mark=in.nextInt();
s.addCourse(new Course(course,mark));
}
as.add(s);
}
for(Student st:as) {
System.out.println(st);
}
}
}

public String nextLine() {
    if (hasNextPattern == linePattern())
        return getCachedResult();
    clearCaches();

    String result = findWithinHorizon(linePattern, 0);
    if (result == null)
        throw new NoSuchElementException("No line found");
    MatchResult mr = this.match();
    String lineSep = mr.group(1);
    if (lineSep != null)
        result = result.substring(0, result.length() - lineSep.length());
    if (result == null)
        throw new NoSuchElementException();
    else
        return result;
}


    看源码，nextLine() 首先就进行了下一个模块的判断，hasNextPattern为空，自然报错