java - 扫描文件并将其分配给对象数组时获取 "Mismatch error"

Question

给定一个学生花名册文件，其中第一行是类(class)中的学生人数，在接下来的几行中，我提供了他们的姓名、ID 和年龄，如下所示:

    5
    Mary, 1010, 15
    Ben, 1119, 16
    Sam, 2278, 15
    Alex, 3245, 15
    Mia, 4448, 16

我应该创建一个学生对象数组，但当我尝试编译代码时收到“不匹配错误”。

我已经尝试了以下方法，但我不确定我的代码有什么问题。

public class Classroom_Runner{
public static void main(String[] args)throws Exception{

File roster = new File("info.txt");
Scanner scanFile = new Scanner(roster);
Scanner scanInput = new Scanner(System.in);
//roster.split(", ");

//String insideFile = "";
int sizeClass = 0;
Classroom[] Students = new Classroom[0];

while(scanFile.hasNext()){
    sizeClass =scanFile.nextInt();
    String name = scanFile.next(); //<-- This would be line 35
    int ID = scanFile.nextInt();
    int age = scanFile.nextInt();

    Classroom student = new Classroom( name, age, ID);

}
    for(int i = 0; i<Students.length;i++){
            System.out.println(Students[i]);}
}
}

实际输出是:

    Exception in thread "main" java.util.InputMismatchException
            at Classroom_Runner.main(Classroom_Runner.java:35)

但预期输出应该是:

    Mary, 1010, 15
    Ben, 1119, 16
    Sam, 2278, 15
    Alex, 3245, 15
    Mia, 4448, 16

Answer 1

        sizeClass =scanFile.nextInt();
        String name = scanFile.next(); 

        String temp = scanFile.next();
        temp = temp.substring(0, temp.length() -1);

        int realID = Integer.parseInt(temp);

        //rest of your code

您应该去掉结尾的逗号，以便以正确的格式捕获整数。