自定义Exception

本文改编自http://blog.csdn.net/stellaah/article/details/6738424

[总结]

1.自定义异常:
　　class 异常类名 extends Exception {
        public 异常类名(String msg) {
            super(msg);
        }
    }
2.标识可能抛出的异常:
　　throws 异常类名1,异常类名2
3.捕获异常:
    try{} catch(异常类名 y){} catch(异常类名 y){}
4.方法解释:
    getMessage()         //输出异常的信息
    printStackTrace()    //输出导致异常更为详细的信息

[代码]

 // 自定义异常
 class ZeroException extends Exception {
     public ZeroException(String msg) {
         super(msg);
     }
 }

 class NegtiveException extends Exception {
     public NegtiveException(String msg) {
         super(msg);
     }
 }
 // 自定义异常 End

 class Calculate {
     public int shang(int x, int y) throws ZeroException,NegtiveException {
         if (y < 0) {
             throw new NegtiveException("您输入的是" + y + ",规定除数不能为负数!");// 抛出异常
         }
         if (y == 0) {
             throw new ZeroException("您输入的是" + y + ",除数不能为0!");
         }

         int m = x / y;
         return m;
     }
 }

 // main
 public class AppTest {
     public static void main(String[] args) {
         Calculate calculate = new Calculate();
         // 捕获异常
         try {
             System.out.println("商=" + calculate.shang(1, -3));
         } catch (ZeroException e) {
             System.out.println(e.getMessage());
             e.printStackTrace();
         } catch (NegtiveException e) {
             System.out.println(e.getMessage());
         }
     }
 }