JSP中封装业务的java bean -DBcon

[qq_36228113]

org.apache.jasper.JasperException: An exception occurred processing JSP page /title.jsp at line 13

10: <tr><td>ISBN</td><td>书名</td><td>版本</td><td>出版时间</td><td>价格</td></tr>
11: <%
12: Connection dbCon= dbcon.getConnction();
13: Statement stmt=dbCon.createStatement();
14: ResultSet rs = stmt.executeQuery("select * from titles");
15: while (rs.next()) {
16: %>


Stacktrace:
org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:505)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:416)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:342)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:267)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)


root cause

java.lang.NullPointerException
org.apache.jsp.title_jsp._jspService(title_jsp.java:74)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:374)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:342)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:267)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)


note The full stack trace of the root cause is available in the Apache Tomcat/6.0.18 logs.

求大神看看这是什么原因造成的！！！！