HTTP Status 500 - An exception occurred processing JSP page /Student.jsp at line 34 type Exception report message An exception occurred processing JSP page /Student.jsp at line 34 description The server encountered an internal error that prevented it from fulfilling this request. exception org.apache.jasper.JasperException: An exception occurred processing JSP page /Student.jsp at line 34 31: ResultSet rs=null; 32: //通过ConnDB创建一个Connection对象,用于执行对数据库的连接操作 33: conn=ConnDB.connection(); 34: stat=conn.createStatement(); 35: rs=stat.executeQuery("select * from Student"); 36: %> 37: <br> Stacktrace: org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:579) org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:476) org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:396) org.apache.jasper.servlet.JspServlet.service(JspServlet.java:340) javax.servlet.http.HttpServlet.service(HttpServlet.java:729) org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) root cause java.lang.NullPointerException org.apache.jsp.Student_jsp._jspService(Student_jsp.java:152) org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70) javax.servlet.http.HttpServlet.service(HttpServlet.java:729) org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:438) org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:396) org.apache.jasper.servlet.JspServlet.service(JspServlet.java:340) javax.servlet.http.HttpServlet.service(HttpServlet.java:729) org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) note The full stack trace of the root cause is available in the Apache Tomcat/8.0.52 logs.
时间: 2023-11-23 12:06:30 浏览: 206
An error occurred during local report processing: report definition has an invalid target namespace
根据异常信息,可以看出在 JSP 页面的第 34 行代码处发生了异常,具体是 `java.lang.NullPointerException`,即空指针异常。这可能是由于在执行查询语句之前,没有成功创建或获取 `conn` 和 `stat` 这两个数据库连接对象,导致在调用 `stat.executeQuery()` 方法时抛出了空指针异常。
您可以检查以下几个方面:
1. 确认数据库连接参数是否正确,比如数据库地址、端口、用户名、密码等是否正确;
2. 确认数据库是否正常运行,比如是否已经启动、是否存在指定的表等;
3. 检查代码中是否有逻辑错误,比如对象的创建和使用顺序是否正确、是否遗漏了某些必要的步骤等。
如果以上步骤都没有解决问题,可以尝试通过查看 Tomcat 日志文件中的详细错误信息,来更进一步地调试问题。
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