Java基础学习14

异常处理

程序员查错网站http://stackoverflow.com/

程序异常处理关键字：try、catch、finally、throw、throws

1、异常的处理流程；

2、异常的处理格式；

3、异常处理的模型。

//程序异常
public class Day14 {
    public static void main(String[] args) {
        System.out.println("开始");
        try {
            System.out.println("运行"+(10/0));
        }catch (ArithmeticException e){
         e.printStackTrace();
        }
        System.out.println("结束");
    }
}

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//程序异常
public class Day14 {
    public static void main(String[] args) {
        System.out.println("开始");
        try {
            System.out.println("运行"+(10/0));
        }catch (ArithmeticException e){
         e.printStackTrace();
        }finally {
            System.out.println("finally");
        }
        System.out.println("结束");
    }
}

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class MyMath{
    //此处明确告诉用户该方法上会有异常
    public static int div(int x,int y)throws Exception{
        return x/y;
    }
}
public class Test21 {
    public static void main(String[] args) {
        try {
            System.out.println(MyMath.div(10,0));
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

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//程序员查错网站http://stackoverflow.com/
//自定义错误
class AddException extends Exception{
    public AddException(String msg){
        super(msg);
    }
}
public class Test23 {
    public static void main(String[] args) throws Exception{
        if ((10+20) == 30){
            throw new AddException("错误的相加操作！");
        }
    }
}

== 30){
throw new AddException(“错误的相加操作！”);
}
}
}