All Fed4FIRE tutorials

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: ${tutorial.image} [in template "be/iminds/ilabt/f4ftut/views/tutorials.ftl" at line 49, column 35] ~ Reached through: #nested [in template "be/iminds/ilabt/f4ftut/views/base.ftl" in macro "page" at line 23, column 1] ~ Reached through: @base.page pageTitle="Fed4FIRE Tutori... [in template "be/iminds/ilabt/f4ftut/views/tutorials.ftl" at line 3, column 1] ---- Java stack trace (for programmers): ---- freemarker.core.InvalidReferenceException: [... Exception message was already printed; see it above ...] at freemarker.core.InvalidReferenceException.getInstance(InvalidReferenceException.java:131) at freemarker.core.EvalUtil.coerceModelToString(EvalUtil.java:355) at freemarker.core.Expression.evalAndCoerceToString(Expression.java:82) at freemarker.core.DollarVariable.accept(DollarVariable.java:41) at freemarker.core.Environment.visit(Environment.java:324) at freemarker.core.MixedContent.accept(MixedContent.java:54) at freemarker.core.Environment.visitByHiddingParent(Environment.java:345) at freemarker.core.IteratorBlock$IterationContext.executeNestedBlockInner(IteratorBlock.java:268) at freemarker.core.IteratorBlock$IterationContext.executeNestedBlock(IteratorBlock.java:220) at freemarker.core.IteratorBlock$IterationContext.accept(IteratorBlock.java:194) at freemarker.core.Environment.visitIteratorBlock(Environment.java:572) at freemarker.core.IteratorBlock.acceptWithResult(IteratorBlock.java:78) at freemarker.core.IteratorBlock.accept(IteratorBlock.java:64) at freemarker.core.Environment.visit(Environment.java:324) at freemarker.core.MixedContent.accept(MixedContent.java:54) at freemarker.core.Environment.visitByHiddingParent(Environment.java:345) at freemarker.core.IfBlock.accept(IfBlock.java:48) at freemarker.core.Environment.visit(Environment.java:324) at freemarker.core.MixedContent.accept(MixedContent.java:54) at freemarker.core.Environment.visit(Environment.java:324) at freemarker.core.Environment.invokeNestedContent(Environment.java:546) at freemarker.core.BodyInstruction.accept(BodyInstruction.java:56) at freemarker.core.Environment.visit(Environment.java:324) at freemarker.core.MixedContent.accept(MixedContent.java:54) at freemarker.core.Environment.visit(Environment.java:324) at freemarker.core.Macro$Context.runMacro(Macro.java:184) at freemarker.core.Environment.invoke(Environment.java:701) at freemarker.core.UnifiedCall.accept(UnifiedCall.java:84) at freemarker.core.Environment.visit(Environment.java:324) at freemarker.core.MixedContent.accept(MixedContent.java:54) at freemarker.core.Environment.visit(Environment.java:324) at freemarker.core.Environment.process(Environment.java:302) at freemarker.template.Template.process(Template.java:325) at io.dropwizard.views.freemarker.FreemarkerViewRenderer.render(FreemarkerViewRenderer.java:73) at io.dropwizard.views.ViewMessageBodyWriter.writeTo(ViewMessageBodyWriter.java:76) at io.dropwizard.views.ViewMessageBodyWriter.writeTo(ViewMessageBodyWriter.java:23) at org.glassfish.jersey.message.internal.WriterInterceptorExecutor$TerminalWriterInterceptor.invokeWriteTo(WriterInterceptorExecutor.java:265) at org.glassfish.jersey.message.internal.WriterInterceptorExecutor$TerminalWriterInterceptor.aroundWriteTo(WriterInterceptorExecutor.java:250) at org.glassfish.jersey.message.internal.WriterInterceptorExecutor.proceed(WriterInterceptorExecutor.java:162) at org.glassfish.jersey.server.internal.JsonWithPaddingInterceptor.aroundWriteTo(JsonWithPaddingInterceptor.java:106) at org.glassfish.jersey.message.internal.WriterInterceptorExecutor.proceed(WriterInterceptorExecutor.java:162) at org.glassfish.jersey.server.internal.MappableExceptionWrapperInterceptor.aroundWriteTo(MappableExceptionWrapperInterceptor.java:86) at org.glassfish.jersey.message.internal.WriterInterceptorExecutor.proceed(WriterInterceptorExecutor.java:162) at org.glassfish.jersey.message.internal.MessageBodyFactory.writeTo(MessageBodyFactory.java:1130) at org.glassfish.jersey.server.ServerRuntime$Responder.writeResponse(ServerRuntime.java:711) at org.glassfish.jersey.server.ServerRuntime$Responder.processResponse(ServerRuntime.java:444) at org.glassfish.jersey.server.ServerRuntime$Responder.process(ServerRuntime.java:434) at org.glassfish.jersey.server.ServerRuntime$2.run(ServerRuntime.java:329) at org.glassfish.jersey.internal.Errors$1.call(Errors.java:271) at org.glassfish.jersey.internal.Errors$1.call(Errors.java:267) at org.glassfish.jersey.internal.Errors.process(Errors.java:315) at org.glassfish.jersey.internal.Errors.process(Errors.java:297) at org.glassfish.jersey.internal.Errors.process(Errors.java:267) at org.glassfish.jersey.process.internal.RequestScope.runInScope(RequestScope.java:317) at org.glassfish.jersey.server.ServerRuntime.process(ServerRuntime.java:305) at org.glassfish.jersey.server.ApplicationHandler.handle(ApplicationHandler.java:1154) at org.glassfish.jersey.servlet.WebComponent.serviceImpl(WebComponent.java:471) at org.glassfish.jersey.servlet.WebComponent.service(WebComponent.java:425) at org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:383) at org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:336) at org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:223) at io.dropwizard.jetty.NonblockingServletHolder.handle(NonblockingServletHolder.java:49) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1669) at org.eclipse.jetty.servlets.UserAgentFilter.doFilter(UserAgentFilter.java:83) at org.eclipse.jetty.servlets.GzipFilter.doFilter(GzipFilter.java:364) at io.dropwizard.jetty.BiDiGzipFilter.doFilter(BiDiGzipFilter.java:132) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1652) at io.dropwizard.servlets.ThreadNameFilter.doFilter(ThreadNameFilter.java:29) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1652) at io.dropwizard.jersey.filter.AllowedMethodsFilter.handle(AllowedMethodsFilter.java:43) at io.dropwizard.jersey.filter.AllowedMethodsFilter.doFilter(AllowedMethodsFilter.java:38) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1652) at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:585) at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1127) at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:515) at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1061) at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:141) at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:97) at com.codahale.metrics.jetty9.InstrumentedHandler.handle(InstrumentedHandler.java:240) at io.dropwizard.jetty.RoutingHandler.handle(RoutingHandler.java:51) at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:97) at org.eclipse.jetty.server.handler.RequestLogHandler.handle(RequestLogHandler.java:95) at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:97) at org.eclipse.jetty.server.handler.StatisticsHandler.handle(StatisticsHandler.java:159) at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:97) at org.eclipse.jetty.server.Server.handle(Server.java:499) at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:310) at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:257) at org.eclipse.jetty.io.AbstractConnection$2.run(AbstractConnection.java:540) at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:635) at org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:555) at java.lang.Thread.run(Thread.java:745)