在布署的润乾web发布包启动时，总是报个 InputStream cannot be null 异常，但这个异常不影响报表的运行， 即便如此，每次启动时看着一堆stacktrace还是感觉很不舒服。
Stack Trace 详情：
[2010-11-23 15:25:25] runqianReportLogger : [DEBUG] - : InputStream cannot be null
错误来源：InputStream cannot be null
: InputStream cannot be null
错误来源：InputStream cannot be null
at com.runqian.report4.semantics.SemanticsManager.readXMLStream(Unknown Source:174)
at com.runqian.report4.view.ReportServlet.loadConfig(Unknown Source:364)
at com.runqian.report4.view.ReportServlet.loadConfig(Unknown Source:95)
at com.runqian.report4.view.ReportServlet.init(Unknown Source:83)
(...)
Caused by: java.lang.IllegalArgumentException: InputStream cannot be null
at javax.xml.parsers.DocumentBuilder.parse(DocumentBuilder.java:94)
at com.runqian.report4.semantics.SemanticsManager.readXMLStream(Unknown Source:171)
... 30 more
DEBUG [main] (Unknown Source:22) - : InputStream cannot be null
错误来源：InputStream cannot be null
: InputStream cannot be null
错误来源：InputStream cannot be null
at com.runqian.report4.semantics.SemanticsManager.readXMLStream(Unknown Source:174)
at com.runqian.report4.view.ReportServlet.loadConfig(Unknown Source:364)
at com.runqian.report4.view.ReportServlet.loadConfig(Unknown Source:95)
at com.runqian.report4.view.ReportServlet.init(Unknown Source:83)
(...)
Caused by: java.lang.IllegalArgumentException: InputStream cannot be null
at javax.xml.parsers.DocumentBuilder.parse(DocumentBuilder.java:94)
at com.runqian.report4.semantics.SemanticsManager.readXMLStream(Unknown Source:171)
... 30 more
错误很明显，缺少语义层文件
错误来源：InputStream cannot be null
at com.runqian.report4.semantics.SemanticsManager.readXMLStream(Unknown Source:174)
找到了错误，解决方法就很简单了，指定正确的语义层文件即可。
打开 WEB-INF 下面的 reportConfig.xml 查找以下XML片断：
在发布报表时，如果没有选择主义层文件，润乾会自动为你生成一个 /WEB-INF/demo.xml 的默认值，
而这个文件根本不存在，所以才会报 InputStream cannot be null 的异常。
如果应用中没有用到语义层文件， 重新设置正确的文件路径，如果没有用到，将此段代码注释或删除即可。
<config>
<name>semanticsFile</name>
<value>/WEB-INF/demo.xml</value>
</config>
重启应用，异常排除，控制台又干净了~