我尝试写的一个上传文件的程序老是报myupload.upload();行有错,请帮忙看看,谢谢!

Question

贴下具体异常信息
另外 myupload.upload(); 这个做了些什么

Answer 1

具体异常如下:我是参照书上敲的，基本跟书一样，可就是调试不过去。java.lang.NullPointerException
at com.jspsmart.upload.SmartUpload.upload(SmartUpload.java:215)
at servlet.Upload.doPost(Upload.java:33)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:710)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:269)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:210)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:174)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:117)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:108)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:151)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:870)
at org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.processConnection(Http11BaseProtocol.java:665)
at org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:528)
at org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFollowerWorkerThread.java:81)
at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:685)
at java.lang.Thread.run(Thread.java:595)

Answer 2

at servlet.Upload.doPost(Upload.java:33) 看看33行是啥！

Answer 3

我是不是应在servlet里实现doget而不是dopost

Answer 4

<form name="form1"  enctype="multipart/form-data" action="./servlet/Upload" method="post"> 当然是POST,上传不可能个是GET

Answer 5

第33行就是myupload.upload();