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: ${article.webUrl} [in template "list.ftl" at line 217, column 67] ---- Java stack trace (for programmers): ---- freemarker.core.InvalidReferenceException: [... Exception message was already printed; see it above ...] at freemarker.core.InvalidReferenceException.getInstance(InvalidReferenceException.java:134) at freemarker.core.EvalUtil.coerceModelToTextualCommon(EvalUtil.java:486) at freemarker.core.EvalUtil.coerceModelToStringOrMarkup(EvalUtil.java:406) at freemarker.core.EvalUtil.coerceModelToStringOrMarkup(EvalUtil.java:375) at freemarker.core.DollarVariable.calculateInterpolatedStringOrMarkup(DollarVariable.java:104) at freemarker.core.DollarVariable.accept(DollarVariable.java:63) at freemarker.core.Environment.visit(Environment.java:344) at freemarker.core.Environment.visit(Environment.java:350) at freemarker.core.SwitchBlock.accept(SwitchBlock.java:79) at freemarker.core.Environment.visit(Environment.java:380) at freemarker.core.IteratorBlock$IterationContext.executedNestedContentForCollOrSeqListing(IteratorBlock.java:321) at freemarker.core.IteratorBlock$IterationContext.executeNestedContent(IteratorBlock.java:271) at freemarker.core.IteratorBlock$IterationContext.accept(IteratorBlock.java:244) at freemarker.core.Environment.visitIteratorBlock(Environment.java:654) at freemarker.core.IteratorBlock.acceptWithResult(IteratorBlock.java:108) at freemarker.core.IteratorBlock.accept(IteratorBlock.java:94) at freemarker.core.Environment.visit(Environment.java:344) at freemarker.core.Environment.visit(Environment.java:350) at freemarker.core.Environment.process(Environment.java:323) at freemarker.template.Template.process(Template.java:383) at com.gzmzb.mzb.module.publish.service.PublishServiceImpl.generateHtml(PublishServiceImpl.java:647) at com.gzmzb.mzb.module.publish.service.PublishServiceImpl.lanmuPublish(PublishServiceImpl.java:332) at com.gzmzb.mzb.module.publish.service.PublishServiceImpl.lambda$lanmuPublishInBackground$1(PublishServiceImpl.java:667) at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:572) at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:317) at com.alibaba.ttl.TtlRunnable.run(TtlRunnable.java:60) at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1144) at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:642) at java.base/java.lang.Thread.run(Thread.java:1583)