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@Configuration

public class WebMvcConfig implements WebMvcConfigurer {

    @Override

    public void addResourceHandlers(ResourceHandlerRegistry registry) {

        // 映射 /upload/** 到项目根目录下的 upload 文件夹

        registry.addResourceHandler("/upload/**")

                .addResourceLocations("file:" + System.getProperty("user.dir") + "/upload/");

    }

}