一、HandlerInterceptorAdapter类
Springboot 的拦截器概念上和Filter 很像,拦截发送到 Controller 的请求和给出的响应;HandlerInterceptorAdapter类提供了请求处理的3个方法;
//拦截于请求刚进入时,进行判断,需要boolean返回值,如果返回true将继续执行,如果返回false,将不进行执行。一般用于登录校验
public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception { return true; }
//拦截于方法成功返回后,视图渲染前,可以对modelAndView进行操作 public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, @Nullable ModelAndView modelAndView) throws Exception { }
//拦截于方法成功返回后,视图渲染前,可以进行成功返回的日志记录 public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, @Nullable Exception ex) throws Exception { }
//不是HandlerInterceptor的接口实现,是AsyncHandlerInterceptor的,AsyncHandlerInterceptor实现了HandlerInterceptor
public void afterConcurrentHandlingStarted(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception { }
二、鉴权AuthInterceptor
继承HandlerInterceptorAdapter类,重写了preHandle方法,对请求登录人角色进行权限鉴定;
@Slf4j public class AuthInterceptor extends HandlerInterceptorAdapter { @Override public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception { request.setCharacterEncoding("UTF-8");
if (true) { return super.preHandle(request, response, handler); } throw new AuthException(EnumResult.PERMISSION_ERROR); } }
三、注册拦截器
注册拦截器很简单,只需要配置一个类,使其实现 WebMvcConfigurer 接口即可;其中还可以设定多个不同的拦截器,并且映射到不同的 url 地址上。
@EnableWebMvc
@Configuration
public class InterceptorConfig implements WebMvcConfigurer {
@Override
public void addInterceptors(InterceptorRegistry registry) {
registry.addInterceptor(new AuthInterceptor())//添加拦截器
.addPathPatterns("/**") .excludePathPatterns("/login");
}
}
注:addPathPatterns("/**")对所有请求都拦截;excludePathPatterns("/login")方法是排除登录访问路径;