The following has evaluated to null or missing:

七月 14, 2016 2:19:25 下午 freemarker.log._JDK14LoggerFactory$JDK14Logger error
嚴重: Error executing FreeMarker template
FreeMarker template error:
The following has evaluated to null or missing:
==> module  [in template "view/addMoudle.html" at line 12, column 45]

Tip: If the failing expression is known to be legally null/missing, either specify a default value with myOptionalVar!myDefault, or use <#if myOptionalVar??>when-present<#else>when-missing</#if>. (These only cover the last step of the expression; to cover the whole expression, use parenthessis: (myOptionVar.foo)!myDefault, (myOptionVar.foo)??

The failing instruction (FTL stack trace):
----------
==> ${module.module_id?default("")}  [in template "view/addMoudle.html" at line 12, column 43]
----------

Java stack trace (for programmers):

 

正確處理方法：1對象不能為空，2值也不能為空，給個默認值。