java.lang.NullPointerException
at com.fr.web.core.FormSessionIDInfor.resolveBlockInterval(Unknown Source)
at com.fr.web.core.FormSessionIDInfor.resolveVariable(Unknown Source)
at com.fr.web.session.SessionIDInfo$SessionIDInforNameSpace.getVariable(SessionIDInfo.java)
at com.fr.base.DefaultNameSpace.resolveFromThreadContext(DefaultNameSpace.java)
at com.fr.base.DefaultNameSpace.getVariable(DefaultNameSpace.java)
at com.fr.script.Calculator$NameSpaceChain.getVariable(Calculator.java)
at com.fr.script.Calculator.resolveVariableInCE(Calculator.java)
at com.fr.parser.BlockIntervalLiteral.eval(BlockIntervalLiteral.java)
at com.fr.parser.BinaryExpression.eval(BinaryExpression.java)
at com.fr.script.Calculator.eval(Calculator.java)
