The field file exceeds its maximum permitted size of 1048576 bytes.
解决方法：
Caused by: java.lang.IllegalStateException: org.apache.tomcat.util.http.fileupload.FileUploadBase$FileSizeLimitExceededException: The field file exceeds its maximum permitted size of 1048576 bytes.
因为springboot默认每个文件的配置最大为1Mb，单次请求的文件的总数不能大于10Mb
可以在application.yml配置文件中上传文件大小限制，我的springboot版本是1.5.8.RELEASE
spring:
http:
multipart:
max-file-size: 100Mb
max-request-size: 500Mb
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