Spring Boot实现功能的统一详解

public class LoginInterceptor implements HandlerInterceptor {
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        HttpSession session = request.getSession(false);
        if (session != null && session.getAttribute("user") != null) {
            return true;
        }
        response.setStatus(401);
        return false;
    }
}

@Configuration
public class AppConfig implements WebMvcConfigurer {
    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        registry.addInterceptor(new LoginInterceptor())
                .addPathPatterns("/**") // 拦截所有的接口
                .excludePathPatterns("/**/login.html"); // 排除的接口
    }
}

@ControllerAdvice
@ResponseBody
public class ErrorAdvice {
    @ExceptionHandler(NullPointerException.class)
    public Object nullPointerException(NullPointerException e) {
        HashMap<String, Object> map = new HashMap<>();
        map.put("success",200);
        map.put("status",-1);
        map.put("message","空指针异常!");
        return map;
    }
}

@RestController
@RequestMapping("/user")
public class UserController {
    @RequestMapping("/hi")
    public String say() {
        Object object = null;
        int i = object.hashCode();
        return "Hello";
    }
}

@ControllerAdvice
public class ResponseAdvice implements ResponseBodyAdvice {
    /**
     * 内容是否重写, 返回true表示重写
     */
    @Override
    public boolean supports(MethodParameter returnType, Class converterType) {
        return true;
    }
    @Override
    public Object beforeBodyWrite(Object body, MethodParameter returnType, MediaType selectedContentType, Class selectedConverterType, ServerHttpRequest request, ServerHttpResponse response) {
        // 统一数据格式的封装
        HashMap<String, Object> result = new HashMap<>();
        result.put("success",200);
        result.put("status",1);
        result.put("data",body);
        return result;
    }
}

@RestController
@RequestMapping("/user")
public class UserController {
    @RequestMapping("/index")
    public Object index() {
        User user = new User();
        user.setUsername("SpringAOP");
        user.setPassword("123456");
        return user;
    }
}