@ExceptionHandler(Exception.class)和@ControllerAdvice

第一种，直接在Controller层写@ExceptionHandler注解，对于指定异常，可以处理并返回一个视图或者body：

@Controller
public class HelloWorld {

    @RequestMapping("test")
    public String test(int flag) throws FileNotFoundException {
        if (1 == flag) {
            throw new FileNotFoundException("文件找不到");
        }
        if (2 == flag) {
            int i = 1 / 0;
        }
        return "hello";
    }

    @ExceptionHandler(IOException.class)
    public ModelAndView h(Exception e, HttpServletRequest req, HttpServletResponse resp, HttpSession sesseion) {
        ModelAndView modelAndView = new ModelAndView();
        modelAndView.setViewName("hello");
        modelAndView.addObject("name", e.getMessage());
        return modelAndView;
    }

    @ResponseBody
    @ExceptionHandler(ArithmeticException.class)
    public String h1(Exception e, HttpServletRequest req, HttpServletResponse resp, HttpSession sesseion) {
        return req.getRequestURI() + "抛出异常" + e.getClass().getName() + e.getMessage();
    }

}

第二种，全局异常处理，通过@ControllerAdvice对所有Controller进行切面通知，可以指定父类
@ExceptionHandler可以指定父类异常

@ControllerAdvice(assignableTypes = HelloWorld.class)
public class ExceptionHanlderClass {

    @ResponseBody
    @ExceptionHandler(Exception.class)
    public String handleExceptions(Exception e, HttpServletRequest req){
        return req.getRequestURI() + "抛出一个异常" + e.getClass().getName() + e.getMessage();
    }
}