我試圖運行的servlet其上傳的文件，但得到以下錯誤

-1

import java.io.File; 
import java.io.IOException; 
import java.io.PrintWriter; 
import java.util.Iterator; 
import java.util.List; 

import javax.servlet.http.HttpServlet; 
import javax.servlet.http.HttpServletRequest; 
import javax.servlet.http.HttpServletResponse; 

import org.apache.commons.fileupload.FileItem; 
import org.apache.commons.fileupload.FileItemFactory; 
import org.apache.commons.fileupload.FileUploadException; 
import org.apache.commons.fileupload.disk.DiskFileItemFactory; 
import org.apache.commons.fileupload.servlet.ServletFileUpload; 

public class TestServlets extends HttpServlet { 

private static final long serialVersionUID = 1L; 

public void doGet(HttpServletRequest request, HttpServletResponse response) 
     throws IOException { 
    doPost(request, response); 
} 

public void doPost(HttpServletRequest request, HttpServletResponse response) 
     throws IOException { 
    response.setContentType("text/html"); 
    PrintWriter out = response.getWriter(); 

    out.println("Hello<br/>"); 

    boolean isMultipartContent = ServletFileUpload 
      .isMultipartContent(request); 
    if (!isMultipartContent) { 
     out.println("You are not trying to upload<br/>"); 
     return; 
    } 
    out.println("You are trying to upload<br/>"); 

    FileItemFactory factory = new DiskFileItemFactory(); 
    ServletFileUpload upload = new ServletFileUpload(factory); 
    try { 
     List<FileItem> fields = upload.parseRequest(request); 
     out.println("Number of fields: " + fields.size() + "<br/><br/>"); 
     Iterator<FileItem> it = fields.iterator(); 
     if (!it.hasNext()) { 
      out.println("No fields found"); 
      return; 
     } 
     out.println("<table border=\"1\">"); 
     while (it.hasNext()) { 
      out.println("<tr>"); 
      FileItem fileItem = it.next(); 
      boolean isFormField = fileItem.isFormField(); 
      if (isFormField) { 
       out.println("<td>regular form field</td><td>FIELD NAME: " 
         + fileItem.getFieldName() + "<br/>STRING: " 
         + fileItem.getString()); 
       out.println("</td>"); 
      } else { 
       out.println("<td>file form field</td><td>FIELD NAME: " 
         + fileItem.getFieldName() + "<br/>STRING: " 
         + fileItem.getString() + "<br/>NAME: " 
         + fileItem.getName() + "<br/>CONTENT TYPE: " 
         + fileItem.getContentType()     
                +"<br/>SIZE(BYTES): " 
         + fileItem.getSize() + "<br/>TO STRING: " 
         + fileItem.toString()); 
       out.println("</td>"); 
      } 
      out.println("</tr>"); 
     } 
     out.println("</table>"); 
    } catch (FileUploadException e) { 
     e.printStackTrace(); 
    } 
} 
}

錯誤代碼我試圖運行的servlet其上傳的文件，但得到以下錯誤

>Mar 27, 2014 2:28:00 PM org.apache.catalina.core.StandardWrapperValve invoke 
>SEVERE: Servlet.service() for servlet [TestServlets] in context with path [/First] threwexception >[Servlet execution threw an exception] with root cause 
    >java.lang.ClassNotFoundException: javax.servlet.http.HttpServletRequest 
    > at java.net.URLClassLoader$1.run(Unknown Source) 
    > at java.net.URLClassLoader$1.run(Unknown Source) 
    > at java.security.AccessController.doPrivileged(Native Method) 
    > at java.net.URLClassLoader.findClass(Unknown Source) 
    > at java.lang.ClassLoader.loadClass(Unknown Source) 
    > at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source) 
    > at java.lang.ClassLoader.loadClass(Unknown Source) 
    > at org.apache.commons.fileupload.servlet.ServletFileUpload. 
    >    isMultipartContent(ServletFileUpload.java:68) 
    > at TestServlets.doPost(TestServlets.java:31) 
    > at javax.servlet.http.HttpServlet.service(HttpServlet.java:641) 
    > at javax.servlet.http.HttpServlet.service(HttpServlet.java:722) 
    > at org.apache.catalina.core.ApplicationFilterChain. 
    >   internalDoFilter(ApplicationFilterChain.java:305) 
    > at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210) 
    > at LogFilter.doFilter(LogFilter.java:35) 
    > 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:225) 
    > at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:169) 
    > at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472) 
    > at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:168) 
    > at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:98) 
    > at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:927) 
    > at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118) 
    > at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407) 
    > at org.apache.coyote.http11.AbstractHttp11Processor. 
    >    process(AbstractHttp11Processor.java:999) 
    > at org.apache.coyote.AbstractProtocol$ 
    >    AbstractConnectionHandler.process(AbstractProtocol.java:565) 
    > at org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.run(AprEndpoint.java:1812) 
    > at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) 
    > at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) 
    > at java.lang.Thread.run(Unknown Source)

來源

2014-03-27 posix

但檢查提供的一些代碼示例。 – RMachnik

http://stackoverflow.com/a/18082387/1225526 - 可能重複 – Karthigeyan