可自定义异常，如下所示：
@SuppressWarnings("serial")
public class MyException extends Exception{
private static final String exceptionMsg = "哎呀，我异常了";
public MyException(){
super(exceptionMsg);
}
public MyException(String message) {
super(message);
}
}
public class ExceptionTest {
public static void main(String[] args) {
try {
double result = getResult(10,0);
} catch(MyException e){
e.printStackTrace();
}
/**catch (Exception e) {
if(e instanceof MyException){
System.out.println("just test");
}
}*/
}
public static double getResult(int num1, int num2) throws MyException{
if(num2 == 0){
throw new MyException("不可以为0");
}
double result = num1/num2;
return result;
}
}