作者： 來源： 發布時間：FreeMarker template error (DEBUG mode; use RETHROW in production!):
The following has evaluated to null or missing:
==> field.date [in template "ms:custom:/show_solution_TL.html" at line 83, column 137]
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Tip: It's the step after the last dot that caused this error, not those before it.
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Tip: If the failing expression is known to legally refer to something that's sometimes null or missing, either specify a default value like myOptionalVar!myDefault, or use <#if myOptionalVar??>when-present<#else>when-missing. (These only cover the last step of the expression; to cover the whole expression, use parenthesis: (myOptionalVar.foo)!myDefault, (myOptionalVar.foo)??
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FTL stack trace ("~" means nesting-related):
- Failed at: ${field.date?string("yyyy-MM-dd")} [in template "ms:custom:/show_solution_TL.html" at line 83, column 135]
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Java stack trace (for programmers):
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freemarker.core.InvalidReferenceException: [... Exception message was already printed; see it above ...]
at freemarker.core.InvalidReferenceException.getInstance(InvalidReferenceException.java:134)
at freemarker.core.UnexpectedTypeException.newDescriptionBuilder(UnexpectedTypeException.java:85)
at freemarker.core.UnexpectedTypeException.