第五次实训异常处理

package TbT;
import java.util.*;
public class doublecircle {
    public static void main(String[] args) {
    Scanner sc=new Scanner(System.in);
    System.out.println("请输入圆的半径");
    double r,s;
    double PI=3.14;
    r=sc.nextInt();
    try {
        s=PI*r*r;
        System.out.println(s);
    }
    catch(Exception e) {
        e.printStackTrace();
        
    }
    }

}

package TbT;
import java.util.*;
public class idcard {
    String id;
    static void avg(String id)throws IllegalArgumentException
{
        if(id.length()!=18) {
            throw new IllegalArgumentException("长度不符合");
        }
        else {
            System.out.println("长度合法");
        }
        
        
    }
    public static void main(String[] args) {
        Scanner sc=new Scanner(System.in);
        idcard p=new idcard();
        try {
            System.out.println("请输入身份证号：");
            p.id=sc.next();
            idcard.avg(p.id);
        }
        catch(IllegalArgumentException e) {
            System.out.println(e);
        }
        
    }

}