SpringBoot 文件上傳遇到的錯誤解決

NoClassDefFoundError-FileUploadException

異常問題：

java.lang.NoClassDefFoundError: org/apache/commons/fileupload/FileUploadException
	java.lang.Class.getDeclaredConstructors0(Native Method)
	java.lang.Class.privateGetDeclaredConstructors(Unknown Source)
	java.lang.Class.getConstructor0(Unknown Source)
	java.lang.Class.newInstance0(Unknown Source)
	java.lang.Class.newInstance(Unknown Source)

解決方案：

在pom.xml中加入

<dependency>
	<groupId>commons-io</groupId>
	<artifactId>commons-io</artifactId>
	<version>2.4</version>
</dependency>
<dependency>
	<groupId>commons-fileupload</groupId>
	<artifactId>commons-fileupload</artifactId>
	<version>1.3.1</version>
</dependency>

這里提供一下maven倉庫鏈接，方便選擇期望的version：
commons-fileupload
commons-io

使用CommonsMultipartFile錯誤

異常報錯：

Caused by: java.lang.IllegalStateException: Cannot convert value of type 'org.springframework.web.multipart.support.StandardMultipartHttpServletRequest$StandardMultipartFile' to required type 'org.springframework.web.multipart.commons.CommonsMultipartFile': no matching editors or conversion strategy found
	at org.springframework.beans.TypeConverterDelegate.convertIfNecessary(TypeConverterDelegate.java:299)
	at org.springframework.beans.TypeConverterDelegate.convertIfNecessary(TypeConverterDelegate.java:99)
	at org.springframework.beans.TypeConverterSupport.doConvert(TypeConverterSupport.java:73)
	at org.springframework.beans.TypeConverterSupport.convertIfNecessary(TypeConverterSupport.java:52)
	at org.springframework.validation.DataBinder.convertIfNecessary(DataBinder.java:692)
	at org.springframework.web.method.annotation.AbstractNamedValueMethodArgumentResolver.resolveArgument(AbstractNamedValueMethodArgumentResolver.java:123)
	... 80 common frames omitted

解決方案：

@RestController
public class TestController {
    @PostMapping("/upload")
    public String upload(HttpServletRequest request, @RequestParam("data") MultipartFile file) {
        // TODO 上傳圖片
        
        return "true";
    }
}

使用MultipartFile接口作為參數，不用使用CommonsMultipartFile參數。