java null报错,java.lang.NullPointerException报错问题

在决策报表的报表快中做了一个分页和超链接

预览的时候点击超链接之后再点击下一页就出现这个报错，请问是什么问题应该怎么解决呢？

java.lang.NullPointerException

at com.fr.report.worksheet.FormElementCase.toHtmlTag(Unknown Source)

at com.fr.web.core.A._D.A(Unknown Source)

at com.fr.web.core.A.OC.A(Unknown Source)

at com.fr.web.core.A.OC.actionCMD(Unknown Source)

at com.fr.web.core.WebActionsDispatcher.dealForActionCMD(Unknown Source)

at com.fr.web.core.WebActionsDispatcher.dealForActionDefaultCmd(Unknown Source)

at com.fr.web.core.WebActionsDispatcher.dealForActionCMD(Unknown Source)

at com.fr.web.core.A.VA.process(Unknown Source)

at com.fr.web.core.ReportDispatcher.dealWithOp(Unknown Source)

at com.fr.web.core.ReportDispatcher.dealWeblet(Unknown Source)

at com.fr.web.core.ReportDispatcher.dealWithRequest(Unknown Source)

at com.fr.web.BaseServlet.doGet(Unknown Source)

at com.fr.web.BaseServlet.doPost(Unknown Source)

at javax.servlet.http.HttpServlet.service(HttpServlet.java:616)

at javax.servlet.http.HttpServlet.service(HttpServlet.java:689)

at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:428)

at org.mortbay.jetty.servlet.WebApplicationHandler.dispatch(WebApplicationHandler.java:473)

at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:568)

at org.mortbay.http.HttpContext.handle(HttpContext.java:1530)

at org.mortbay.jetty.servlet.WebApplicationContext.handle(WebApplicationContext.java:633)

at org.mortbay.http.HttpContext.handle(HttpContext.java:1482)

at org.mortbay.http.HttpServer.service(HttpServer.java:909)

at org.mortbay.http.HttpConnection.service(HttpConnection.java:820)

at org.mortbay.http.HttpConnection.handleNext(HttpConnection.java:986)

at org.mortbay.http.HttpConnection.handle(HttpConnection.java:837)

at org.mortbay.http.SocketListener.handleConnection(SocketListener.java:245)

at org.mortbay.util.ThreadedServer.handle(ThreadedServer.java:357)

at org.mortbay.util.ThreadPool$PoolThread.run(ThreadPool.java:534)