Attributes should be specified via @SpringBootApplication问题解决

Posted 2022-11-11 沉默着忍受

项目场景： 在spring boot启动方法上设置@EnableAutoConfiguration注解，如下所示：

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问题描述：

@EnableAutoConfiguration(exclude = MultipartAutoConfiguration.class)
@SpringBootApplication
public class CloudApplication  extends ServletInitializer

    public static void main(String[] args) 
        SpringApplication.run(CloudApplication.class, args);
    
    @Override
    protected SpringApplicationBuilder configure(SpringApplicationBuilder application) 
        return application.sources(CloudApplication.class);
    

    @Bean(name = "multipartResolver")
    public MultipartResolver multipartResolver() 
        CommonsMultipartResolver resolver = new CommonsMultipartResolver();
        resolver.setDefaultEncoding("UTF-8");
        resolver.setResolveLazily(true);//resolveLazily属性启用是为了推迟文件解析，以在在UploadAction中捕获文件大小异常
        resolver.setMaxInMemorySize(40960);
        resolver.setMaxUploadSize(5 * 1024 * 1024);//上传文件大小 5M 5*1024*1024
        return resolver;
    

这里会发生Attributes should be specified via @SpringBootApplication错误

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原因分析：

经过排查代码发现，@SpringBootApplication注解中已经包含@EnableAutoConfiguration注解，不需要重复定义@EnableAutoConfiguration注解。

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解决方案：

去掉@EnableAutoConfiguration注解，将(exclude = MultipartAutoConfiguration.class)赋予@SpringBootApplication，改进后：

@SpringBootApplication(exclude = MultipartAutoConfiguration.class)
public class CloudApplication  extends ServletInitializer

    public static void main(String[] args) 
        SpringApplication.run(CloudApplication.class, args);
    
    @Override
    protected SpringApplicationBuilder configure(SpringApplicationBuilder application) 
        return application.sources(CloudApplication.class);
    

    @Bean(name = "multipartResolver")
    public MultipartResolver multipartResolver() 
        CommonsMultipartResolver resolver = new CommonsMultipartResolver();
        resolver.setDefaultEncoding("UTF-8");
        resolver.setResolveLazily(true);//resolveLazily属性启用是为了推迟文件解析，以在在UploadAction中捕获文件大小异常
        resolver.setMaxInMemorySize(40960);
        resolver.setMaxUploadSize(5 * 1024 * 1024);//上传文件大小 5M 5*1024*1024
        return resolver;