SpringBoot @ControllerAdvice异常处理

@ControllerAdvice需要与@ExceptionHandler配合使用

@ControllerAdvice放在类上，表明这个类用以处理异常
@ExceptionHandler(XXException.class)则用在具体的方法上，表示处理特定的异常
@ResponseStatus(HttpStatus.BAD_GATEWAY)可以在处理异常后，返回特定的状态

@RestControllerAdvice=@ControllerAdvice+@ResponseBody

栗子：

@GetMapping("ex")
public Map ex(@RequestParam String sss) throws MyException {
    HashMap h = new HashMap();
    h.put("aaa", sss);
    if (sss.equals("ex")) {
        throw new MyException();
    }
    return h;
}

异常类：

public class MyException extends Exception {
}

处理：

@RestControllerAdvice
public class GlobalExceptionHandler {

    @ResponseStatus(HttpStatus.BAD_GATEWAY)
    @ExceptionHandler(MyException.class)
    public Map handler(MyException e, HttpServletRequest httpServletRequest) {
        HashMap map = new HashMap();
        map.put("bbb", "xxxxx");
        return map;
    }
}