在Java中,使用POI來進行excel的讀取和解析是常用的一種做法;在office的excel中存在2007,2003兩種不同的格式,通常情況下是以xls/xlsx的不同後綴來區分的,但用戶可能不知道這個區別,所以會出現格式無法兼容的異常
1. POI
POI源自Apache基金會,是其頂級域名項目, POI提供API給Java程序對Microsoft Office格式檔案讀和寫的功能。
2. Excel 2003和2007之區別
微軟針對Excel在2007版本之後的實現中使用了ooxml的格式來描述內容信息,和之前2003版本的excel在實現上有所區別,故在POI中提供了一個新的類來兼容2007版的excel的讀取和創建過程。
HSSF - 提供讀寫Microsoft Excel格式檔案的功能。
XSSF - 提供讀寫Microsoft Excel OOXML格式檔案的功能。
HSSF,XSSF的功能列表對比
3. 問題描述
在上傳excel文件中,解析excel文件,並解析中出現瞭如下錯誤信息:
Apr 13, 2015 1:29:08 PM org.apache.catalina.core.StandardWrapperValve invoke
SEVERE: Servlet.service() for servlet [appServlet] in context with path [/bsettle] threw exception [Request processing failed; nested exception is org.apache.poi.POIXMLException: org.apache.poi.openxml4j.exceptions.InvalidFormatException: Package should contain a content type part [M1.13]] with root cause
org.apache.poi.openxml4j.exceptions.InvalidFormatException: Package should contain a content type part [M1.13]
at org.apache.poi.openxml4j.opc.ZipPackage.getPartsImpl(ZipPackage.java:203)
at org.apache.poi.openxml4j.opc.OPCPackage.getParts(OPCPackage.java:673)
at org.apache.poi.openxml4j.opc.OPCPackage.open(OPCPackage.java:274)
at org.apache.poi.util.PackageHelper.open(PackageHelper.java:37)
at org.apache.poi.xssf.usermodel.XSSFWorkbook.<init>(XSSFWorkbook.java:258)
at com.creditease.bsettle.basic.controller.BasicDataController.uploadBusinessDept(BasicDataController.java:350)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.springframework.web.method.support.InvocableHandlerMethod.invoke(InvocableHandlerMethod.java:215)
at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:132)
at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:104)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod(RequestMappingHandlerAdapter.java:745)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:685)
at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:80)
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:919)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:851)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:953)
at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:855)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:647)
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:829)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:77)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:106)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.springframework.orm.jpa.support.OpenEntityManagerInViewFilter.doFilterInternal(OpenEntityManagerInViewFilter.java:180)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:106)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:106)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1041)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:603)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:312)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
at java.lang.Thread.run(Thread.java:662)
在用戶操作過程中,上傳excel之後,後臺出現了上述錯誤;針對正常的情況下的excel是沒有問題的;經過分析上傳文件發現,應該是2007和2003文件格式不同導致的問題。
在原有的代碼中, 解析excel的內容如下:
XSSFWorkbook hssfWorkbook = new XSSFWorkbook(file.getInputStream());
由此可知,目前的代碼中只能支持Excel 2007的格式解析,而不能支持2003格式。 故此產生了異常信息.
4. 解決方案
爲了解決針對excel 2003 和 excel 2007 的多種格式,使用如下代碼,提供了良好的兼容性:
Workbook workbook = WorkbookFactory.create(file.getInputStream());
Sheet hssfSheet = workbook.getSheetAt(0); //示意訪問sheet
這裏我們使用了一個抽象類Workbook來訪問所有的格式下的excel,雖然某些特性,比如2007下的內容可能無法正常讀取,但是主要的內容是可以正常讀取的。
5. 總結
對Excel的讀取,主要涉及工作薄、工作薄、行數據、單元格等的處理,POI對97-2003和2007+兩個版本的處理採用不同的類,如下圖所示:
其中:
a)Workbook、Sheet、Row、Cell等爲接口;
b)HSSFWorkbook、HSSFSheet、HSSFRow、HSSFCell爲97-2003版本對應的處理實現類;
c)XSSFWorkbook、XSSFSheet、XSSFRow、XSSFCell爲2007+版本對應的處理實現類;