Calling DisplayTag returns NullPointerException

We've been using DisplayTag for awhile now without any problems, but recently, we had a wonky hdd and so we had to restore some of the stuff on there. Unfortunately, DisplayTag broke and stops everything else when called: Will return with the following error: java.lang.NullPointerException java.lang.Class.forName0(Native Method) java.lang.Class.forName(Class.java:164) org.displaytag.properties.TableProperties.getClassProperty(TableProperties.java:759) org.displaytag.properties.TableProperties.getClassPropertyInstance(TableProperties.java:776) org.displaytag.properties.TableProperties.getRequestHelperFactoryInstance(TableProperties.java:714) org.displaytag.tags.TableTag.initParameters(TableTag.java:715) org.displaytag.tags.TableTag.doStartTag(TableTag.java:600) org.apache.jsp.misc.key_002dtable_jsp._jspService(key_002dtable_jsp.java:113) org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:94) javax.servlet.http.HttpServlet.service(HttpServlet.java:802) org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:324) org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:292) org.apache.jasper.servlet.JspServlet.service(JspServlet.java:236) javax.servlet.http.HttpServlet.service(HttpServlet.java:802) sun.reflect.GeneratedMethodAccessor36.invoke(Unknown Source) sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) java.lang.reflect.Method.invoke(Method.java:585) org.apache.catalina.security.SecurityUtil$1.run(SecurityUtil.java:243) java.security.AccessController.doPrivileged(Native Method) javax.security.auth.Subject.doAsPrivileged(Subject.java:517) org.apache.catalina.security.SecurityUtil.execute(SecurityUtil.java:272) org.apache.catalina.security.SecurityUtil.doAsPrivilege(SecurityUtil.java:161) I'm not quite familiar with Apache Tomcat and Java but I suspect that it has to do with a catalina's security policy. I'm hoping that someone could either confirm this or help point me in the right direction. We're currently on Tomcat 5.
first check for classpath incompatibilities. Clean your web-app dir and deploy afresh

以上就是Calling DisplayTag returns NullPointerException的详细内容,更多请关注web前端其它相关文章!

赞(0) 打赏
未经允许不得转载:web前端首页 » JavaScript 答疑

评论 抢沙发

  • 昵称 (必填)
  • 邮箱 (必填)
  • 网址

前端开发相关广告投放 更专业 更精准

联系我们

觉得文章有用就打赏一下文章作者

支付宝扫一扫打赏

微信扫一扫打赏