apusic应用服务器下的FileUpload问题——我的一次移植测试经历

    在一合作伙伴处进行OA系统移植测试，客户系统采用jsp+javabean开发，部分servlet。有一个公告发布功能，允许上传附件，在tomcat应用服务器下运行正常，在apusic服务器下报空指针异常。

    功能涉及到的文件主要三个：gonggao_add.jsp、gonggao_insert.jsp、
HttpFileUpload.java。其中填写表单、选择附件在gonggao_add.jsp，然后提交到
gonggao_insert.jsp，在gonggao_insert.jsp里用到HttpFileUpload.java。

    报错信息如下，显示问题出在HttpFileUpload.java这个类的parseRequest()方法：

2009-09-04 08:52:13 错误 [apusic.web.dzzw./dzzw] 执行Servlet时发生错误。
java.lang.NullPointerException
	at org.apache.commons.fileupload.MultipartStream
$ItemInputStream.makeAvailable(MultipartStream.java:967)
	at org.apache.commons.fileupload.MultipartStream$ItemInputStream.read
(MultipartStream.java:887)
	at java.io.InputStream.read(InputStream.java:85)
	at org.apache.commons.fileupload.util.Streams.copy(Streams.java:94)
	at org.apache.commons.fileupload.util.Streams.copy(Streams.java:64)
	at org.apache.commons.fileupload.MultipartStream.readBodyData
(MultipartStream.java:593)
	at org.apache.commons.fileupload.MultipartStream.discardBodyData
(MultipartStream.java:619)
	at org.apache.commons.fileupload.MultipartStream.skipPreamble
(MultipartStream.java:638)
	at com.cnblogs.zxub.upload.HttpFileUpload.parseRequest
(HttpFileUpload.java:212)
	at
_jspx._bangong._oa._gonggao._program._gonggao_5finsert__jsp._jspService
(bangong/oa/gonggao/program/gonggao_insert.jsp:29)
	at com.apusic.web.jsp.runtime.HttpJspPageImpl.service(Unknown Source)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:820)
	at com.apusic.web.container.ServletComponent.service(Unknown Source)
	at com.apusic.web.container.WebContainer.invoke(Unknown Source)
	at com.apusic.web.container.WebContainer.invoke(Unknown Source)
	at com.apusic.web.jsp.JspServlet.service(Unknown Source)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:820)
	at com.apusic.web.container.ServletComponent.service(Unknown Source)
	at com.apusic.web.container.WebContainer.invoke(Unknown Source)
	at com.apusic.web.container.WebContainer.processRequest(Unknown
Source)
	at com.apusic.web.http.VirtualHost.processRequest(Unknown Source)
	at com.apusic.web.http.HttpServer.processRequest(Unknown Source)
	at com.apusic.web.http.HttpConnectionHandler.service(Unknown Source)
	at com.apusic.web.http.ConnectionHandler.processRequest(Unknown
Source)
	at com.apusic.web.http.ConnectionHandler.processConnection(Unknown
Source)
	at com.apusic.web.http.ConnectionHandler.run(Unknown Source)
	at com.apusic.util.ThreadPoolImpl$WorkerThread.run(Unknown Source)

    当时由于不知道的原因，HttpFileUpload.java这个文件客户无法提供源码，没办法进行跟踪调试，定位具体出错的位置；

    gonggao_insert.jsp页面部分代码如下：

String filename="";
String newfilename="";

String path="UploadFile/bangong/oa/gonggao";

DiskFileItemFactory factory = new DiskFileItemFactory(); 
factory.setSizeThreshold(4096);

factory.setRepository(new File(application.getRealPath("\\") + path));
HttpFileUpload upload = new HttpFileUpload(factory);
upload.setAllowFileTypes("");
upload.setSizeMax(1000*1024*1024);
List fileItems = upload.parseRequest(request); //异常提示在此报错（gonggao_insert.jsp:29）
Iterator iter = fileItems.iterator();
while(iter.hasNext()){
FileItem fi=(FileItem)iter.next();
String fileName = fi.getName();
File tempFile = new File(fileName);
fileName = tempFile.getName();
String newfileName="";

if(!"".equals(fileName))
{
fileName=fileName.substring(fileName.lastIndexOf("\\")+1,fileName.length());
String Suffix=fileName.substring(fileName.lastIndexOf("."),fileName.length());
uuid.UUID uuid0=new uuid.UUID();
String ID=String.valueOf(uuid0);
newfileName=ID+Suffix;
newfilename+=newfileName+"@@";
filename+=fileName+"@@";
fi.write(new File(application.getRealPath("\\") + path, newfileName));
}
}

    经跟踪gonggao_insert.jsp代码发现，文件中如下代码在tomcat和apusic应用服务器下结果不一致：

application.getRealPath("\\")，但是进行修改后仍然报同样的错误。

    在现场测试发现，gonggao_add.jsp页面中，即便没有选择任何附件，提交后都报异常，增加附件后提交也报异常，异常信息都是一样的。gonggao_insert.jsp页面中，把上传附件相关代码注释掉后，除附件外的其他表单数据可以正常提交保存。

    后来经过跟同事多次沟通，仔细分析了出错信息，终于找到了问题原因和解决办法：删除%apusic_home%\lib\ext\operamasks-third-party.jar后一切OK！

    原因分析：apusic应用服务器为了支持operamasks框架的上传组件，在operamasks-third-party.jar内置了apache fileupload相关类文件，由于apusic应用服务器默认首先加载自带的jar包，导致伙伴OA系统lib下的fileupload.jar里的相关类没有得到加载，而apusic应用服务器自带的fileupload相关类跟伙伴OA系统Lib下版本不一致，导致出现问题。