springboot语言包的过滤器和拦截器的简单实现

 SpringBoot2.0之后拦截器配置需要实现WebMvcConfigure接口

执行顺序:过滤器-->拦截器:preHandle-->controller -->拦截器:视图渲染前-->postHandler-->拦截器:视图渲染-->afterCompletion

@Component
public class LangFilter implements Filter {
    @Override
    public void init(FilterConfig filterConfig) throws ServletException {

    }

    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
        Locale locale = request.getLocale();
        System.out.println("过滤器: " + locale);
        chain.doFilter(request,response);
    }

    @Override
    public void destroy() {

    }
}

@Component
public class LangInterceptor implements HandlerInterceptor {
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        Locale locale = request.getLocale();
        System.out.println("拦截器: " + locale);
        return true;
    }

    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {

    }

    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {

    }
}

注册拦截器,实现拦截器最重要的步骤(和)启动类处于同一目录下):

@Configuration
public class WebMvcConfig extends WebMvcConfigurerAdapter {
    // 这里使用autowired无法实现拦截器
    @Bean
    LangInterceptor langInterceptor() {
        return new LangInterceptor();
    }

    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        registry.addInterceptor(langInterceptor()).addPathPatterns("/**");
    }
}