这个是在搭建cloud+boot…+mybatis…+freemarker.模板 报错的错

这个错 说的是找不到 或者空数据

freemarker.core.InvalidReferenceException: The following has evaluated to null or missing:
==> user  [in template "user.ftl" at line 19, column 19]

----
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</#if>. (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: ${user.userId}  [in template "user.ftl" at line 19, column 17]
----
	at freemarker.core.InvalidReferenceException.getInstance(InvalidReferenceException.java:134) ~[freemarker-2.3.27-incubating.jar:2.3.27]
	at freemarker.core.UnexpectedTypeException.newDesciptionBuilder(UnexpectedTypeException.java:85) ~[freemarker-2.3.27-incubating.jar:2.3.27]
	at freemarker.core.UnexpectedTypeException.<init>(UnexpectedTypeException.java:48) ~[freemarker-2.3.27-incubating.jar:2.3.27]
	at freemarker.core.NonHashException.<init>(NonHashException.java:49) ~[freemarker-2.3.27-incubating.jar:2.3.27]
	at freemarker.core.Dot._eval(Dot.java:48) ~[freemarker-2.3.27-incubating.jar:2.3.27]
	at freemarker.core.Expression.eval(Expression.java:83) ~[freemarker-2.3.27-incubating.jar:2.3.27]
	at freemarker.core.DollarVariable.calculateInterpolatedStringOrMarkup(DollarVariable.java:96) ~[freemarker-2.3.27-incubating.jar:2.3.27]
	at freemarker.core.DollarVariable.accept(DollarVariable.java:59) ~[freemarker-2.3.27-incubating.jar:2.3.27]
	at freemarker.core.Environment.visit(Environment.java:361) [freemarker-2.3.27-incubating.jar:2.3.27]
	at freemarker.core.IteratorBlock$IterationContext.executedNestedContentForCollOrSeqListing(IteratorBlock.java:317) [freemarker-2.3.27-incubating.jar:2.3.27]
	at freemarker.core.IteratorBlock$IterationContext.executeNestedContent(IteratorBlock.java:271) [freemarker-2.3.27-incubating.jar:2.3.27]
	at freemarker.core.IteratorBlock$IterationContext.accept(IteratorBlock.java:242) [freemarker-2.3.27-incubating.jar:2.3.27]
	at freemarker.core.Environment.visitIteratorBlock(Environment.java:635) [freemarker-2.3.27-incubating.jar:2.3.27]
	at freemarker.core.IteratorBlock.acceptWithResult(IteratorBlock.java:107) [freemarker-2.3.27-incubating.jar:2.3.27]
	at freemarker.core.IteratorBlock.accept(IteratorBlock.java:93) [freemarker-2.3.27-incubating.jar:2.3.27]
	at freemarker.core.Environment.visit(Environment.java:325) [freemarker-2.3.27-incubating.jar:2.3.27]
	at freemarker.core.Environment.visit(Environment.java:331) [freemarker-2.3.27-incubating.jar:2.3.27]
	at freemarker.core.Environment.process(Environment.java:304) [freemarker-2.3.27-incubating.jar:2.3.27]
	at freemarker.template.Template.process(Template.java:382) [freemarker-2.3.27-incubating.jar:2.3.27]
	at org.springframework.web.servlet.view.freemarker.FreeMarkerView.processTemplate(FreeMarkerView.java:368) [spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.springframework.web.servlet.view.freemarker.FreeMarkerView.doRender(FreeMarkerView.java:285) [spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.springframework.web.servlet.view.freemarker.FreeMarkerView.renderMergedTemplateModel(FreeMarkerView.java:235) [spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.springframework.web.servlet.view.AbstractTemplateView.renderMergedOutputModel(AbstractTemplateView.java:167) [spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.springframework.web.servlet.view.AbstractView.render(AbstractView.java:303) [spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.springframework.web.servlet.DispatcherServlet.render(DispatcherServlet.java:1286) [spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.springframework.web.servlet.DispatcherServlet.processDispatchResult(DispatcherServlet.java:1041) [spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:984) [spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:901) [spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970) [spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:861) [spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:687) [javax.servlet-api-3.1.0.jar:3.1.0]
	at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846) [spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:790) [javax.servlet-api-3.1.0.jar:3.1.0]
	at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:841) [jetty-servlet-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1650) [jetty-servlet-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.websocket.server.WebSocketUpgradeFilter.doFilter(WebSocketUpgradeFilter.java:206) [websocket-server-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1637) [jetty-servlet-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.springframework.boot.web.filter.ApplicationContextHeaderFilter.doFilterInternal(ApplicationContextHeaderFilter.java:55) [spring-boot-1.5.9.RELEASE.jar:1.5.9.RELEASE]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1637) [jetty-servlet-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.springframework.boot.actuate.trace.WebRequestTraceFilter.doFilterInternal(WebRequestTraceFilter.java:110) [spring-boot-actuator-1.5.9.RELEASE.jar:1.5.9.RELEASE]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1637) [jetty-servlet-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99) [spring-web-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1637) [jetty-servlet-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.springframework.web.filter.HttpPutFormContentFilter.doFilterInternal(HttpPutFormContentFilter.java:108) [spring-web-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1637) [jetty-servlet-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:81) [spring-web-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1637) [jetty-servlet-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:197) [spring-web-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1637) [jetty-servlet-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.springframework.boot.actuate.autoconfigure.MetricsFilter.doFilterInternal(MetricsFilter.java:106) [spring-boot-actuator-1.5.9.RELEASE.jar:1.5.9.RELEASE]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1637) [jetty-servlet-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:533) [jetty-servlet-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:143) [jetty-server-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:548) [jetty-security-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:132) [jetty-server-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:190) [jetty-server-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:1595) [jetty-server-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:188) [jetty-server-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1253) [jetty-server-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:168) [jetty-server-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:473) [jetty-servlet-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:1564) [jetty-server-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:166) [jetty-server-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1155) [jetty-server-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:141) [jetty-server-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:132) [jetty-server-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.server.Server.handle(Server.java:561) [jetty-server-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:334) [jetty-server-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:251) [jetty-server-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.io.AbstractConnection$ReadCallback.succeeded(AbstractConnection.java:279) [jetty-io-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:104) [jetty-io-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.io.ChannelEndPoint$2.run(ChannelEndPoint.java:124) [jetty-io-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:679) [jetty-util-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.util.thread.QueuedThreadPool$2.run(QueuedThreadPool.java:597) [jetty-util-9.4.7.v20170914.jar:9.4.7.v20170914]
	at java.lang.Thread.run(Thread.java:748) [na:1.8.0_144]

2019-04-10 20:30:15.698  WARN 9416 --- [tp1289334945-25] org.eclipse.jetty.server.HttpChannel     : /list/user

org.springframework.web.util.NestedServletException: Request processing failed; nested exception is freemarker.core.InvalidReferenceException: The following has evaluated to null or missing:
==> user  [in template "user.ftl" at line 19, column 19]

----
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</#if>. (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: ${user.userId}  [in template "user.ftl" at line 19, column 17]
----
	at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:982) ~[spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:861) ~[spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:687) ~[javax.servlet-api-3.1.0.jar:3.1.0]
	at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846) ~[spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:790) ~[javax.servlet-api-3.1.0.jar:3.1.0]
	at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:841) ~[jetty-servlet-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1650) ~[jetty-servlet-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.websocket.server.WebSocketUpgradeFilter.doFilter(WebSocketUpgradeFilter.java:206) ~[websocket-server-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1637) ~[jetty-servlet-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.springframework.boot.web.filter.ApplicationContextHeaderFilter.doFilterInternal(ApplicationContextHeaderFilter.java:55) ~[spring-boot-1.5.9.RELEASE.jar:1.5.9.RELEASE]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1637) ~[jetty-servlet-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.springframework.boot.actuate.trace.WebRequestTraceFilter.doFilterInternal(WebRequestTraceFilter.java:110) ~[spring-boot-actuator-1.5.9.RELEASE.jar:1.5.9.RELEASE]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1637) ~[jetty-servlet-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99) ~[spring-web-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1637) ~[jetty-servlet-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.springframework.web.filter.HttpPutFormContentFilter.doFilterInternal(HttpPutFormContentFilter.java:108) ~[spring-web-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1637) ~[jetty-servlet-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:81) ~[spring-web-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1637) ~[jetty-servlet-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:197) ~[spring-web-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1637) ~[jetty-servlet-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.springframework.boot.actuate.autoconfigure.MetricsFilter.doFilterInternal(MetricsFilter.java:106) ~[spring-boot-actuator-1.5.9.RELEASE.jar:1.5.9.RELEASE]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1637) ~[jetty-servlet-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:533) ~[jetty-servlet-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:143) ~[jetty-server-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:548) ~[jetty-security-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:132) ~[jetty-server-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:190) ~[jetty-server-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:1595) ~[jetty-server-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:188) ~[jetty-server-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1253) ~[jetty-server-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:168) ~[jetty-server-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:473) ~[jetty-servlet-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:1564) ~[jetty-server-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:166) ~[jetty-server-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1155) ~[jetty-server-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:141) ~[jetty-server-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:132) ~[jetty-server-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.server.Server.handle(Server.java:561) ~[jetty-server-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:334) ~[jetty-server-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:251) [jetty-server-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.io.AbstractConnection$ReadCallback.succeeded(AbstractConnection.java:279) [jetty-io-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:104) [jetty-io-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.io.ChannelEndPoint$2.run(ChannelEndPoint.java:124) [jetty-io-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:679) [jetty-util-9.4.7.v20170914.jar:9.4.7.v20170914]
	at org.eclipse.jetty.util.thread.QueuedThreadPool$2.run(QueuedThreadPool.java:597) [jetty-util-9.4.7.v20170914.jar:9.4.7.v20170914]
	at java.lang.Thread.run(Thread.java:748) [na:1.8.0_144]
Caused by: freemarker.core.InvalidReferenceException: The following has evaluated to null or missing:
==> user  [in template "user.ftl" at line 19, column 19]

----
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</#if>. (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: ${user.userId}  [in template "user.ftl" at line 19, column 17]
----
	at freemarker.core.InvalidReferenceException.getInstance(InvalidReferenceException.java:134) ~[freemarker-2.3.27-incubating.jar:2.3.27]
	at freemarker.core.UnexpectedTypeException.newDesciptionBuilder(UnexpectedTypeException.java:85) ~[freemarker-2.3.27-incubating.jar:2.3.27]
	at freemarker.core.UnexpectedTypeException.<init>(UnexpectedTypeException.java:48) ~[freemarker-2.3.27-incubating.jar:2.3.27]
	at freemarker.core.NonHashException.<init>(NonHashException.java:49) ~[freemarker-2.3.27-incubating.jar:2.3.27]
	at freemarker.core.Dot._eval(Dot.java:48) ~[freemarker-2.3.27-incubating.jar:2.3.27]
	at freemarker.core.Expression.eval(Expression.java:83) ~[freemarker-2.3.27-incubating.jar:2.3.27]
	at freemarker.core.DollarVariable.calculateInterpolatedStringOrMarkup(DollarVariable.java:96) ~[freemarker-2.3.27-incubating.jar:2.3.27]
	at freemarker.core.DollarVariable.accept(DollarVariable.java:59) ~[freemarker-2.3.27-incubating.jar:2.3.27]
	at freemarker.core.Environment.visit(Environment.java:361) ~[freemarker-2.3.27-incubating.jar:2.3.27]
	at freemarker.core.IteratorBlock$IterationContext.executedNestedContentForCollOrSeqListing(IteratorBlock.java:317) ~[freemarker-2.3.27-incubating.jar:2.3.27]
	at freemarker.core.IteratorBlock$IterationContext.executeNestedContent(IteratorBlock.java:271) ~[freemarker-2.3.27-incubating.jar:2.3.27]
	at freemarker.core.IteratorBlock$IterationContext.accept(IteratorBlock.java:242) ~[freemarker-2.3.27-incubating.jar:2.3.27]
	at freemarker.core.Environment.visitIteratorBlock(Environment.java:635) ~[freemarker-2.3.27-incubating.jar:2.3.27]
	at freemarker.core.IteratorBlock.acceptWithResult(IteratorBlock.java:107) ~[freemarker-2.3.27-incubating.jar:2.3.27]
	at freemarker.core.IteratorBlock.accept(IteratorBlock.java:93) ~[freemarker-2.3.27-incubating.jar:2.3.27]
	at freemarker.core.Environment.visit(Environment.java:325) ~[freemarker-2.3.27-incubating.jar:2.3.27]
	at freemarker.core.Environment.visit(Environment.java:331) ~[freemarker-2.3.27-incubating.jar:2.3.27]
	at freemarker.core.Environment.process(Environment.java:304) ~[freemarker-2.3.27-incubating.jar:2.3.27]
	at freemarker.template.Template.process(Template.java:382) ~[freemarker-2.3.27-incubating.jar:2.3.27]
	at org.springframework.web.servlet.view.freemarker.FreeMarkerView.processTemplate(FreeMarkerView.java:368) ~[spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.springframework.web.servlet.view.freemarker.FreeMarkerView.doRender(FreeMarkerView.java:285) ~[spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.springframework.web.servlet.view.freemarker.FreeMarkerView.renderMergedTemplateModel(FreeMarkerView.java:235) ~[spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.springframework.web.servlet.view.AbstractTemplateView.renderMergedOutputModel(AbstractTemplateView.java:167) ~[spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.springframework.web.servlet.view.AbstractView.render(AbstractView.java:303) ~[spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.springframework.web.servlet.DispatcherServlet.render(DispatcherServlet.java:1286) ~[spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.springframework.web.servlet.DispatcherServlet.processDispatchResult(DispatcherServlet.java:1041) ~[spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:984) ~[spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:901) ~[spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970) ~[spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	... 53 common frames omitted

原因 是我的mybatis里 没给 驼峰命名法报的错

原：

解决

可以向上面图上这样写 也可以 在 mybatis 里加上驼峰命名