@Override 把这个标签 干掉！方法前添加这个便签的意义你还没学到，编译器自己会自动生成，但是请你干掉他！

import java.util.Scanner;

public class Demo1 {

public void Area() {

// TODO Auto-generated method stub

Scanner a = new Scanner(System.in);

int w = a.nextInt();

Scanner b = new Scanner(System.in);

int l = b.nextInt();

double area = w*l;

System.out.println(area);

}

public void Cir() {

Scanner a = new Scanner(System.in);

int w = a.nextInt();

Scanner b = new Scanner(System.in);

int l = b.nextInt();

int cir = 2*(w+l);

System.out.println(cir);

}

}

你这部分代码应该是没问题，我补充了个main，执行了一下，可以执行，完整代码：

//包名

package com.practice;

//导入Scanner

import java.util.Scanner;

public class HellWorld {

public static void main(String[] args) {

// TODO Auto-generated method stub

        HellWorld  rec1 = new HellWorld();

        rec1.Area();

        rec1.Cir();

}

public void Area() {

// TODO Auto-generated method stub

Scanner a = new Scanner(System.in);

int w = a.nextInt();

Scanner b = new Scanner(System.in);

int l = b.nextInt();

double area = w*l;

System.out.println(area);

}

//@Override

public void Cir() {

// TODO Auto-generated method stub

Scanner a = new Scanner(System.in);

int w = a.nextInt();

Scanner b = new Scanner(System.in);

int l = b.nextInt();

int cir = 2*(w+l);

System.out.println(cir);

}

}