springboot项目中的拦截器

我们在提供 API 的时候，经常需要对 API 进行统一的拦截，比如进行接口的安全性校验。

创建一个拦截器类：ApiInterceptor，并实现 HandlerInterceptor 接口：

public class ApiInterceptor implements HandlerInterceptor {
    //请求之前
    @Override
    public boolean preHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o) throws Exception {
        System.out.println("进入拦截器");
        return true;
    }
    //请求时
    @Override
    public void postHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, ModelAndView modelAndView) throws Exception {

    }
    //请求完成
    @Override
    public void afterCompletion(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, Exception e) throws Exception {

    }
}

@SpringBootConfiguration 注解的类继承 WebMvcConfigurationSupport 类，并重写 addInterceptors 方法，将 ApiInterceptor 拦截器类添加进去，代码如下：

@SpringBootConfiguration
public class WebConfig extends WebMvcConfigurationSupport{

    @Override
    protected void addInterceptors(InterceptorRegistry registry) {
        super.addInterceptors(registry);
        registry.addInterceptor(new ApiInterceptor());
    }
}