使用poi读取excel时出现两个错误，记录一下：
java.lang.ClassNotFoundException:org.apache.xmlbeans.XmlObject
org.apache.commons.collections4.ListValuedMap

1、报错内容：java.lang.ClassNotFoundException:org.apache.xmlbeans.XmlObject
缺少相关的jar包：
pom中加入：

<dependency>
			<groupId>org.apache.xmlbeans</groupId>
			<artifactId>xmlbeans</artifactId>
			<version>2.4.0</version>
		</dependency>

	更新maven即可。

2、报错内容：org.apache.commons.collections4.ListValuedMap
导入以下jar包
由于我的poi是3.17的，

<dependency>  
    <groupId>org.apache.commons</groupId>  
    <artifactId>commons-collections4</artifactId>  
    <version>4.1</version>  
</dependency>  

3、The supplied data appears to be in the OLE2 Format. You are calling the part of POI that deals with OOXML (Office Open XML) Documents. You need to call a different part of POI to process this data (eg HSSF instead of XSSF)

主要原因是xssf只能读取.xslx的excel
hssf只能读取.xsl的excel
查看一下文件的后缀是否正确