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type Exception reportmessage description The server encountered an internal error () that prevented it from fulfilling this request.exception org.apache.jasper.JasperException
org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:512)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:395)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:314)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:264)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
root cause java.lang.NullPointerException
org.apache.jsp.main_jsp._jspService(main_jsp.java:138)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:97)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:334)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:314)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:264)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
note The full stack trace of the root cause is available in the Apache Tomcat/5.5.20 logs.这是什么问题？怎么解决？

解决方案 »

  1.   

    java.lang.NullPointerException 空指针异常
    页面上有取值，或其它操作
    结果没有取出值
    详情看\Tomcat \work\Catalina\localhost下的
    main_jsp.java:138文件
    仔细看看
      

  2.   

    package org.apache.jsp;import javax.servlet.*;
    import javax.servlet.http.*;
    import javax.servlet.jsp.*;
    import com.business.*;
    import com.common.util.*;
    import com.common.resource.*;
    import java.util.*;
    import com.web.util.*;public final class main_jsp extends org.apache.jasper.runtime.HttpJspBase
        implements org.apache.jasper.runtime.JspSourceDependent {  private static java.util.List _jspx_dependants;  static {
        _jspx_dependants = new java.util.ArrayList(4);
        _jspx_dependants.add("/WEB-INF/struts-bean.tld");
        _jspx_dependants.add("/WEB-INF/struts-html.tld");
        _jspx_dependants.add("/WEB-INF/Page.tld");
        _jspx_dependants.add("/include/include.inc");
      }  private org.apache.jasper.runtime.TagHandlerPool _jspx_tagPool_myTag_place_name;  public Object getDependants() {
        return _jspx_dependants;
      }  public void _jspInit() {
        _jspx_tagPool_myTag_place_name = org.apache.jasper.runtime.TagHandlerPool.getTagHandlerPool(getServletConfig());
      }  public void _jspDestroy() {
        _jspx_tagPool_myTag_place_name.release();
      }  public void _jspService(HttpServletRequest request, HttpServletResponse response)
            throws java.io.IOException, ServletException {    JspFactory _jspxFactory = null;
        PageContext pageContext = null;
        HttpSession session = null;
        ServletContext application = null;
        ServletConfig config = null;
        JspWriter out = null;
        Object page = this;
        JspWriter _jspx_out = null;
        PageContext _jspx_page_context = null;
        try {
          _jspxFactory = JspFactory.getDefaultFactory();
          response.setContentType("text/html; charset=GB2312");
          pageContext = _jspxFactory.getPageContext(this, request, response,
           null, true, 8192, true);
          _jspx_page_context = pageContext;
          application = pageContext.getServletContext();
          config = pageContext.getServletConfig();
          session = pageContext.getSession();
          out = pageContext.getOut();
          _jspx_out = out;      out.write("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\">\r\n");
          out.write("<HTML>\r\n");
          out.write("<HEAD>\r\n");
          out.write("\r\n");
          out.write("\r\n");
          out.write("\r\n");
          out.write("\r\n");
          out.write(" \r\n");
          out.write("  \r\n");
          out.write(" \r\n");
          out.write("\r\n");
          out.write("\r\n");
          out.write("<META http-equiv=\"Content-Type\" content=\"text/html; charset=GB2312\">\r\n");
          out.write("<META name=\"GENERATOR\" content=\"IBM WebSphere Studio\">\r\n");
          out.write("<LINK href=\"");
          out.print(request.getContextPath());
          out.write("/style/style.css\" rel=\"stylesheet\" type=\"text/css\">\r\n");
          out.write("<script language=javascript src=\"");
          out.print(request.getContextPath());
          out.write("/js/layer.js\"></script>\r\n");
          out.write("<script language=javascript src=\"");
          out.print(request.getContextPath());
          out.write("/js/style.js\"></script>\r\n");
          out.write("<script language=javascript src=\"");
          out.print(request.getContextPath());
          out.write("/js/univerify.js\"></script>\r\n");
          out.write("<script language=javascript src=\"");
          out.print(request.getContextPath());
          out.write("/js/manage.js\"></script>\r\n");
          out.write("<script language=javascript src=\"");
          out.print(request.getContextPath());
          out.write("/js/DateInput.js\"></script>\r\n");
          out.write("\r\n");
          out.write("<title></title>\r\n");
          out.write("<base target=\"_self\">\r\n");
          out.write("</head>\r\n");
          out.write("<div align=center>\r\n");
          out.write("<body>\r\n");
          if (_jspx_meth_myTag_place_0(_jspx_page_context))
            return;
          out.write("\r\n");
          out.write("\r\n");
          out.write("<TABLE class=table-top03 cellSpacing=0 cellPadding=0 width=\"100%\" align=center border=0>\r\n");
          out.write("\t<TBODY>\r\n");
          out.write("\t\t<TR>\r\n");
          out.write("\t\t\t<TD>\r\n");
          out.write("\t\t\t<TABLE cellSpacing=0 cellPadding=0 width=\"100%\" border=0>\r\n");
          out.write("\t\t\t\t<TBODY>\r\n");
          out.write("\t\t\t\t\t<TR>\r\n");
          out.write("\t\t\t\t\t\t<TD width=\"3%\"></TD>\r\n");
          out.write("\t\t\t\t\t\t<TD width=\"90%\">最新库存信息</TD>\r\n");
          out.write("\t\t\t\t\t\t<TD align=right width=\"7%\">\r\n");
          out.write("\t\t\t\t\t\t\t<IMG class=img01 onmouseover=\"this.style.cursor = 'hand';\"onclick=showdetailMin(this,searchTable1) height=12 src=\"images/title_minimize.gif\" width=12>&nbsp; \r\n");
          out.write("\t\t\t\t\t\t\t<IMG class=img01 onmouseover=\"this.style.cursor = 'hand';\"onclick=showdetailMax(this,searchTable1) height=12\tsrc=\"images/title_maximize.gif\" width=12>&nbsp;\r\n");
          out.write("\t\t\t\t\t\t</TD>\r\n");
          out.write("\t\t\t\t\t</TR>\r\n");
          out.write("\t\t\t\t</TBODY>\r\n");
          out.write("\t\t\t</TABLE>\r\n");
          out.write("\t\t\t</TD>\r\n");
          out.write("\t\t</TR>\r\n");
          out.write("\t</TBODY>\r\n");
          out.write("</TABLE>\r\n");
          out.write("<TABLE class=\"table-min01\" align=\"center\" width=100%\tborder=0 cellpadding=0 cellspacing=0 id=searchTable1>\r\n");
          out.write("\t<TR>\r\n");
          out.write("\t\t<TD class=\"min-td01\">货品名称</TD>\r\n");
          out.write("\t\t<TD class=\"min-td01\">货品类型</TD>\r\n");
          out.write("\t\t<TD class=\"min-td01\">库存数量</TD>\r\n");
          out.write("\t</TR>\r\n");

    GoodsTypeBusiness bs = new GoodsTypeBusiness();
    KuCunBusiness cs = new KuCunBusiness();
    List list = cs.select();
    for(int i=0;i<9;i++){
    if(i<list.size()){
    HashMap map = (HashMap)list.get(i);              out.write("\r\n");
          out.write("\t<tr>\r\n");
          out.write("\t\t<TD class=\"min-td02\">");
          out.print(WebTools.showEx(map.get("NAME")));
          out.write("&nbsp;</TD>\r\n");
          out.write("\t\t<TD class=\"min-td02\">");
          out.print(bs.getNameById(WebTools.showEx(map.get("TYPE"))));
          out.write("&nbsp;</TD>\r\n");
          out.write("\t\t\t\t\r\n");
          out.write("\t\t<TD class=\"min-td02\">");
          out.print(WebTools.showEx(map.get("NUM")));
          out.write("&nbsp;</TD>\r\n");
          out.write("\t</tr>\r\n");
    }else{
          out.write("\r\n");
          out.write("\t<tr>\r\n");
          out.write("\t\t<TD class=\"min-td02\">&nbsp;</TD>\r\n");
          out.write("\t\t<TD class=\"min-td02\">&nbsp;</TD>\r\n");
          out.write("\t\t<TD class=\"min-td02\">&nbsp;</TD>\r\n");
          out.write("\t</tr>\r\n");
          out.write("\r\n");
    }}
          out.write("\r\n");
          out.write("</TABLE>\r\n");
          out.write("\r\n");
          out.write("<TABLE class=table-top03 cellSpacing=0 cellPadding=0 width=\"100%\" align=center border=0>\r\n");
          out.write("\t<TBODY>\r\n");
          out.write("\t\t<TR>\r\n");
          out.write("\t\t\t<TD>\r\n");
          out.write("\t\t\t<TABLE cellSpacing=0 cellPadding=0 width=\"100%\" border=0>\r\n");
          out.write("\t\t\t\t<TBODY>\r\n");
          out.write("\t\t\t\t\t<TR>\r\n");
          out.write("\t\t\t\t\t\t<TD width=\"3%\"></TD>\r\n");
          out.write("\t\t\t\t\t\t<TD width=\"90%\">最新货品信息</TD>\r\n");
          out.write("\t\t\t\t\t\t<TD align=right width=\"7%\">\r\n");
          out.write("\t\t\t\t\t\t\t<IMG class=img01 onmouseover=\"this.style.cursor = 'hand';\"onclick=showdetailMin(this,searchTable2) height=12 src=\"images/title_minimize.gif\" width=12>&nbsp; \r\n");
          out.write("\t\t\t\t\t\t\t<IMG class=img01 onmouseover=\"this.style.cursor = 'hand';\"onclick=showdetailMax(this,searchTable2) height=12\tsrc=\"images/title_maximize.gif\" width=12>&nbsp;\r\n");