目前POI的最新发布版本是3.10_FINAL.该版本保护的jar包有：
| Maven artifactId | Prerequisites | JAR |
|---|---|---|
| poi | commons-logging, commons-codec, log4j | poi-version-yyyymmdd.jar |
| poi-scratchpad | poi | poi-scratchpad-version-yyyymmdd.jar |
| poi-ooxml | poi, poi-ooxml-schemas | poi-ooxml-version-yyyymmdd.jar |
| poi-ooxml-schemas | xmlbeans | poi-ooxml-schemas-version-yyyymmdd.jar |
| poi-examples | poi, poi-scratchpad, poi-ooxml | poi-examples-version-yyyymmdd.jar |
| ooxml-schemas | xmlbeans | ooxml-schemas-1.1.jar |
很多人都困惑POI那么多Jar到底应该导入哪一个。
实际上很多时候我们只利用POI来操作Excel。甚至只用xls这一种格式。
那么就没有必要全部都导入了。具体应该使用哪个JAR包请参考以下内容：
Component Map
The Apache POI distribution consists of support for many document file formats. This support is provided in several Jar files. Not all of the Jars are needed for every format. The following tables show the relationships between POI components, Maven repository tags, and the project's Jar files.
| Component | Application type | Maven artifactId | Notes |
|---|---|---|---|
| POIFS | OLE2 Filesystem | poi | Required to work with OLE2 / POIFS based files |
| HPSF | OLE2 Property Sets | poi | |
| HSSF | Excel XLS | poi | For HSSF only, if common SS is needed see below |
| HSLF | PowerPoint PPT | poi-scratchpad | |
| HWPF | Word DOC | poi-scratchpad | |
| HDGF | Visio VSD | poi-scratchpad | |
| HPBF | Publisher PUB | poi-scratchpad | |
| HSMF | Outlook MSG | poi-scratchpad | |
| OpenXML4J | OOXML | poi-ooxml plus one of poi-ooxml-schemas, ooxml-schemas |
Only one schemas jar is needed, see below for differences |
| XSSF | Excel XLSX | poi-ooxml | |
| XSLF | PowerPoint PPTX | poi-ooxml | |
| XWPF | Word DOCX | poi-ooxml | |
| Common SS | Excel XLS and XLSX | poi-ooxml | WorkbookFactory and friends all require poi-ooxml, not just core poi |
当我们只要使用xls格式时、只要导入poi-version-yyyymmdd.jar就可以了。
当我们还要使用xlsx格式、还要导入poi-ooxml-version-yyyymmdd.jar。
至于poi-ooxml-schemas-version-yyyymmdd.jar这个jar基本不太会用到的。（但是个人发现如果不导入这个包 会报错）
当我们需要操作word、ppt、viso、outlook等时需要用到poi-scratchpad-version-yyyymmdd.jar。
当操作excel2007以上的版本的时候，需要导入poi-ooxml-version-yyyymmdd.jar。当我导入之后，的确是可以调用excel2007的操作类了 例如:XSSFWorkbook.可是当项目调试的时候，会报java.lang.ClassNotFoundException: org.apache.xmlbeans.XmlObject 这个错误，在操作office2007还要加入一个包xbean.jar ，原以为导入这个包之后，就万事大吉了。可是接下来又报错了，查资料发现还是需要导入poi-ooxml-schemas-version-yyyymmdd.jar。