class MyException extends Exception { //继续了Exception这个父类

private int detail;

MyException(int a) {

detail = a;}

public String toString() {

return "MyException[" + detail + "]";

}}

class ExceptionDemo {

static void compute(int a) throws MyException {

System.out.println("调用 compute(" + a + ")");

if(a > 10)

throw new MyException(a);

System.out.println("常规退出 ");

}

public static void main(String args[]) {

try {

compute(1);

compute(20);

} catch (MyException e) {

System.out.println("捕捉 " + e); //这样就可以用自己定义的类来捕捉异常了

}}}