FreeMarker template error (DEBUG mode; use RETHROW in production!): The following has evaluated to null or missing: ==> art.extend [in template "李雨_article" at line 171, column 93] ---- Tip: It's the step after the last dot that caused this error, not those before it. ---- 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)?? ---- ---- FTL stack trace ("~" means nesting-related): - Failed at: ${art.extend.bsxm!} [in template "李雨_article" at line 171, column 91] - Reached through: @article [in template "李雨_article" at line 161, column 25] ---- Java stack trace (for programmers): ---- freemarker.core.InvalidReferenceException: [... Exception message was already printed; see it above ...] at freemarker.core.InvalidReferenceException.getInstance(InvalidReferenceException.java:134) at freemarker.core.UnexpectedTypeException.newDescriptionBuilder(UnexpectedTypeException.java:85) at freemarker.core.UnexpectedTypeException.(UnexpectedTypeException.java:48) at freemarker.core.NonHashException.(NonHashException.java:49) at freemarker.core.Dot._eval(Dot.java:48) at freemarker.core.Expression.eval(Expression.java:101) at freemarker.core.DefaultToExpression._eval(DefaultToExpression.java:96) at freemarker.core.Expression.eval(Expression.java:101) at freemarker.core.DollarVariable.calculateInterpolatedStringOrMarkup(DollarVariable.java:100) at freemarker.core.DollarVariable.accept(DollarVariable.java:63) at freemarker.core.Environment.visit(Environment.java:383) at freemarker.core.Environment$NestedElementTemplateDirectiveBody.render(Environment.java:3274) at com.file.system.plugin.freemarker.tags.ArticleTag.execute(ArticleTag.java:92) at freemarker.core.Environment.visit(Environment.java:464) at freemarker.core.UnifiedCall.accept(UnifiedCall.java:102) at freemarker.core.Environment.visit(Environment.java:347) at freemarker.core.Environment.visit(Environment.java:353) at freemarker.core.Environment.process(Environment.java:326) at freemarker.template.Template.process(Template.java:383) at com.file.system.plugin.freemarker.FreemarkerMain.writeHtml(FreemarkerMain.java:157) at com.file.system.plugin.freemarker.TemplateArticle.articlePublish(TemplateArticle.java:219) at com.file.system.plugin.freemarker.TemplateArticle.lambda$executePublish$4(TemplateArticle.java:130) at java.lang.Thread.run(Unknown Source)