如何在java中解决此扫描器方法错误

Question

不工作…如何去除错误…请帮帮我怎么做

是给我错误的扫描仪扫描方法的东西我无法解决这个问题。

如何使用这个扫描器类

import java.util.*;
public class A
{
  class Student
  {
    int i,id,age;
    int m[]=new int[3];
    int tot=0,per;
    String name;

    Scanner scan=new Scanner(System.in);
    Student(int id,String name,int age)
    {
      this.id=id;
      this.name=name;
      this.age=age;
    }
    public void getMarks()
    {
      System.out.println("Enter UR marks-- ");
      for(i=0;i<3;i++)
      {
        System.out.print("n Enter Marks For Sub "+i);
        m[i]=scan.nextInt();
        tot=tot+m[i];
      }
    }
    void display()
    {
      System.out.println("ID-- "+id);
      System.out.println("Name-- "+name);
      System.out.println("Age-- "+age);
      System.out.println("Total-- "+tot);
      System.out.println("Percentage-- "+(per/i));
    }
  }
  public static void main(String[] args)
  {
    Student s1=new Student(101,"jay",20);
    s1.getMarks();
    s1.display();
  }
}

Answer 1

给你:

import java.util.*;
class Student {
int i, id, age;
int m[] = new int[3];
int tot = 0, per;
String name;

Student(int id, String name, int age) {
    this.id = id;
    this.name = name;
    this.age = age;
    }
public void getMarks() {
    Scanner scan = new Scanner(System.in);
    System.out.println("Enter UR marks-- ");
    for (i = 0; i < 3; i++) {
        System.out.print("n Enter Marks For Sub " + i);
        m[i] = scan.nextInt();
        tot = tot + m[i];
      }
   }
void display() {
    System.out.println("ID-- " + id);
    System.out.println("Name-- " + name);
    System.out.println("Age-- " + age);
    System.out.println("Total-- " + tot);
    System.out.println("Percentage-- " + (per / i));
    }
}
public class A {
public static void main(String[] args) {
    Student s1 = new Student(101, "jay", 20);
    s1.getMarks();
    s1.display();
    }
}

一些提示:1)除非需要，永远不要将类声明为其他类的成员。(如您所做的，class Student 在 class A。2)在你想要使用的方法中声明实例化Scanner对象。将其声明为类成员不起任何作用。3)使用完后，始终关闭扫描器。即scan.close()

访问以下链接:

1. 何时使用嵌套类