自定义异常运行实例

/*
    自定义异常：ScoreException
 */
public class ScoreException extends Exception {
    //无参构造
    public ScoreException(){}

    //带参构造
    public ScoreException(String message){
        super(message);
    }
}

/*
    定义教师类
 */
public class Teacher {
    public void checkScore(int score) throws Exception{
        if (score < 0 || score > 100){
            throw new ScoreException("你输入的分数有误");
        }else {
            System.out.println("分数正常");
        }
    }
}

/*
    测试类
 */
import java.util.Scanner;

public class TeacherTest {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        System.out.println("请输入分数：");
        int score = sc.nextInt();

        Teacher t = new Teacher();
        try {
            t.checkScore(score);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

当输入的成绩不在正常的范围内时，会输出异常提醒

请输入分数：
120
com.itheima_02.ScoreException: 你输入的分数有误
    at com.itheima_02.Teacher.checkScore(Teacher.java:6)
    at com.itheima_02.TeacherTest.main(TeacherTest.java:13)