java-----异常

 解决异常的方法：

package 异常;

public class ExceptionDemo1 {
    public static void main(String[] args) {
        System.out.println("开始");
        method();
        System.out.println("结束");
    }
    public static void method(){
        try {
            int[] arr={1,2,3};
            System.out.println(arr[3]);
        }catch(ArrayIndexOutOfBoundsException e){
//            System.out.println("你访问的数组索引不存在");
            e.printStackTrace();
        }

    }
}

package 异常;

import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;


public class ExceptionDemo2 {
    public static void main(String[] args) {
        System.out.println("开始");
        try {
            method();
        } catch (ParseException e) {
            e.printStackTrace();
        }
        System.out.println("结束");
    }
    public static void method() throws ParseException {//格式
        String s="2030-11-10";
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy.MM.dd");
        Date d=sdf.parse(s);//parse这里的异常
    }
}

自定义异常：

package 异常.自定义异常;

public class ScoreException extends Exception {

    public ScoreException(){}
    public ScoreException(String message) {
        super(message);
    }
}

package 异常.自定义异常;

public class Teacher {
    public void checkScore(int score) throws ScoreException {
        if (score<0||score>100) {
            throw new ScoreException("你给的分数有误");
        }else{
            System.out.println("分数正常");
        }
    }
}

package 异常.自定义异常;

import java.util.Scanner;

public class TeacherText {
    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 (ScoreException e) {
            e.printStackTrace();
        }

    }
}