java.lang.NullPointerException帮忙找一下吧?

[xiaofangxwt1]

type Exception report

message Internal Server Error

description The server encountered an internal error (Internal Server Error) that prevented it from fulfilling this request.

exception

java.lang.NullPointerException
at org.apache.jsp.filter_0005fwrite_0005fexcel$jsp._jspService(filter_0005fwrite_0005fexcel$jsp.java:216)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:107)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
at org.apache.jasper.servlet.JspServlet$JspServletWrapper.service(JspServlet.java:201)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:381)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:473)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:247)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:243)
at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:190)
at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566)
at org.apache.catalina.valves.CertificatesValve.invoke(CertificatesValve.java:246)
at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:564)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943)
at org.apache.catalina.core.StandardContext.invoke(StandardContext.java:2347)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:180)
at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566)
at org.apache.catalina.valves.ErrorDispatcherValve.invoke(ErrorDispatcherValve.java:170)
at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:564)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:170)
at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:564)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:468)
at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:564)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:174)
at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943)
at org.apache.catalina.connector.http.HttpProcessor.process(HttpProcessor.java:1027)
at org.apache.catalina.connector.http.HttpProcessor.run(HttpProcessor.java:1125)
at java.lang.Thread.run(Thread.java:536)

请问是那的错误

[pshy]

servlet有没有配好！

[postform999]

把代码贴出来看看吧
应该是有一个值为null的类实例,试图对它执行方法？

[xiaofangxwt1]

POIFSFileSystem fs1 = new POIFSFileSystem(new FileInputStream("d:/mb1.xls"));/*打开EXCEL表*/
HSSFWorkbook wb = new HSSFWorkbook(fs1);/*打开工作薄*/
HSSFSheet sheet = wb.getSheetAt(0);/*打开工作表*/
if(flag==0 && (sel_table.equals("bb_jxyzj_zb")))
{ rsgl.beforeFirst();
if(rsgl.next())
{
if(fields.equals("bz1")){qz=rsgl.getString("bz");}
else{qz = rsgl.getString(fields);}//取表里的字段值
if(qz==null){qz = " ";}
int waq = 0;
waq = col_lie+1;
HSSFRow row = sheet.getRow(hang-1);//在第几行输出
HSSFCell cell = row.getCell((short)waq);//在第几列输出
cell.setEncoding(HSSFCell.ENCODING_UTF_16);//转化为中文
cell.setCellValue(qz);//输出值
FileOutputStream fileOut = new FileOutputStream("d:/QQQ检修月总结.xls");//写出EXCEL表
wb.write(fileOut);
fileOut.close();
}
}

[zhenhexp]

up

[uestc6055]

这样看代码好累，你可以试下单步调试。

[liaohaiying]

有空值

[tiannet]

去filter_0005fwrite_0005fexcel$jsp.java 文件的第 216 行看看出错的地方。
这个文件一般都在work/Catalina/localhost直至你相应的目录中。。

[JavaLiver]

是空指针，楼主可以单步调试一下呀。
不过看楼主的java文件 好象又是jsp生成的哦
那就要调试jsp了，jsp里代码不多 找找其实就行了

[huanbin]

是空指针了啊，
我原来也被这个错郁闷了好久，不过单步调一下就可以了，把可能有值的参数全print出来

[funcreal]

那不是写着呢吗？在216行。
不用单步调试。
但是不是你这个文件，你要去tomcat_home/work/Catalina/localhost里面去找