day29 捕获和抛出异常

异常处理机制

• 抛出异常
• 捕获异常
• 异常处理五个关键字

​ try,catch,finally,throw,throws

package com.exception;

public class Test {
    public static void main(String[] args) {
        //假设要捕获多个异常：从小到大！

            try {
                new Test().test(1, 0);
            } catch (Exception e) {
                e.printStackTrace();
            }

        }
    public void test(int a,int b)throws ArithmeticException{//假设方法中，处理不了这个异常。就在方法上抛出这个异常
        if (b == 0) {//throw   throws
            throw new ArithmeticException();//主动地抛出异常，一般在方法中使用

        }

    }
/*//假设要捕获多个异常：从小到大！
        int a =0;
        int b =1;
    } //catch必须要，finally可以不要，假设有IO,资源，关闭，都放在finally里

        try {//try监控区域
            if (b == 0) {//throw   throws
                throw new ArithmeticException();//主动地抛出异常

            }

            System.out.println(a / b);
        } catch (Error e) {//catch 捕获异常
            System.out.println("Error");
        } catch (Exception e) {//catch 捕获异常
            System.out.println("Exception");
        } catch (Throwable t) {//catch 捕获异常
            System.out.println("Throwable");
        } finally {//处理善后工作
            System.out.println("finally");
        }
* */
}

package com.exception;

public class Test2 {
    public static void main(String[] args) {
        int a = 1;
        int b = 0;
        try {
            System.out.println(a/b);//ctrl+alt+t
        } catch (Exception e) {
            System.exit(1);
            e.printStackTrace();//打印错误的栈信息
        }

    }
}