[Java知识库]springboot自定义拦截器，注册拦截器

具体步骤如下 :

• 编写一个拦截器
• 通过WebMvcConfigurer注册拦截器

1.编写一个拦截器类并实现HandlerInterceptor

@Component
public class HelloInterceptor implements HandlerInterceptor {
	//请求之前调用
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        System.out.println("HelloInterceptor - preHandle");
        return true; //放行，false为不放行

    }

	//请求时调用
    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
        System.out.println("HelloInterceptor - postHandle");
    }

	//请求完后调用
    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
        System.out.println("HelloInterceptor - afterCompletion");
    }
}

2.通过WebMvcConfigurer注册拦截器

@SpringBootConfiguration //声明一个配置类
public class MVCInterceptorConfig implements WebMvcConfigurer {

    //配置拦截器声明

    @Autowired
    HelloInterceptor helloInterceptor;

    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        // Ant路径规则：
        // ? 只能匹配一个字符
        // * 可以匹配多个字符，不能匹配多级路径
        // ** 可以匹配任意字符及路径
        registry.addInterceptor(helloInterceptor).addPathPatterns("/**");
    }
}