KML description template does not handle the empty case gracefully

Only major because it generates a lot of tracebacks when it gets hammered by Google Earth or GWC

2008-12-23 13:53:19,034 WARN [geoserver.kml] - Error occured processing 'description' template.
java.io.IOException: Error occured processing template.
at org.vfny.geoserver.wms.responses.featureInfo.FeatureTemplate.execute(FeatureTemplate.java:269)
at org.vfny.geoserver.wms.responses.featureInfo.FeatureTemplate.description(FeatureTemplate.java:165)
at org.vfny.geoserver.wms.responses.featureInfo.FeatureTemplate.description(FeatureTemplate.java:193)
at org.vfny.geoserver.wms.responses.map.kml.KMLMapTransformer$KMLMapTranslatorSupport.encodePlacemarkDescription(KMLMapTransformer.java:257)
at org.vfny.geoserver.wms.responses.map.kml.KMLMapTransformer$KMLMapTranslatorSupport.encodePlacemark(KMLMapTransformer.java:844)
at org.vfny.geoserver.wms.responses.map.kml.KMLMapTransformer$KMLMapTranslatorSupport.encodePlacemark(KMLMapTransformer.java:808)
at org.vfny.geoserver.wms.responses.map.kml.KMLVectorTransformer$KMLTranslator.encode(KMLVectorTransformer.java:202)
at org.vfny.geoserver.wms.responses.map.kml.KMLVectorTransformer$KMLTranslator.encode(KMLVectorTransformer.java:144)
at org.vfny.geoserver.wms.responses.map.kml.KMLTransformer$KMLTranslator.encodeVectorLayer(KMLTransformer.java:203)
at org.vfny.geoserver.wms.responses.map.kml.KMLTransformer$KMLTranslator.encode(KMLTransformer.java:133)
at org.geotools.xml.transform.TransformerBase$XMLReaderSupport.parse(TransformerBase.java:714)
at org.apache.xalan.transformer.TransformerIdentityImpl.transform(TransformerIdentityImpl.java:484)
at org.geotools.xml.transform.TransformerBase$Task.run(TransformerBase.java:296)
at org.geotools.xml.transform.TransformerBase.transform(TransformerBase.java:129)
at org.geotools.xml.transform.TransformerBase.transform(TransformerBase.java:108)
at org.vfny.geoserver.wms.responses.map.kml.KMLMapProducer.writeTo(KMLMapProducer.java:123)
at org.vfny.geoserver.wms.responses.GetMapResponse.writeTo(GetMapResponse.java:608)
at org.geoserver.ows.adapters.ResponseAdapter.write(ResponseAdapter.java:60)
at org.geoserver.ows.Dispatcher.response(Dispatcher.java:711)
at org.geoserver.ows.Dispatcher.handleRequestInternal(Dispatcher.java:215)
at org.springframework.web.servlet.mvc.AbstractController.handleRequest(AbstractController.java:153)
at org.springframework.web.servlet.mvc.SimpleControllerHandlerAdapter.handle(SimpleControllerHandlerAdapter.java:48)
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:875)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:809)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:571)
at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:501)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:617)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.vfny.geoserver.filters.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:108)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:264)
at org.acegisecurity.intercept.web.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:107)
at org.acegisecurity.intercept.web.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:72)
at org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:274)
at org.acegisecurity.ui.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:110)
at org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:274)
at org.acegisecurity.providers.anonymous.AnonymousProcessingFilter.doFilter(AnonymousProcessingFilter.java:125)
at org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:274)
at org.acegisecurity.ui.basicauth.BasicProcessingFilter.doFilter(BasicProcessingFilter.java:178)
at org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:274)
at org.acegisecurity.context.HttpSessionContextIntegrationFilter.doFilter(HttpSessionContextIntegrationFilter.java:229)
at org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:274)
at org.acegisecurity.util.FilterChainProxy.doFilter(FilterChainProxy.java:148)
at org.acegisecurity.util.FilterToBeanProxy.doFilter(FilterToBeanProxy.java:98)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.geoserver.filters.LoggingFilter.doFilter(LoggingFilter.java:73)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.geoserver.filters.ReverseProxyFilter.doFilter(ReverseProxyFilter.java:163)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.geoserver.filters.GZIPFilter.doFilter(GZIPFilter.java:47)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:286)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:845)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447)
at java.lang.Thread.run(Thread.java:619)
Caused by: freemarker.core.InvalidReferenceException: Expression type is undefined on line 4, column 53 in description.ftl.
at freemarker.core.TemplateObject.assertNonNull(TemplateObject.java:124)
at freemarker.core.TemplateObject.invalidTypeException(TemplateObject.java:134)
at freemarker.core.Dot._getAsTemplateModel(Dot.java:78)
at freemarker.core.Expression.getAsTemplateModel(Expression.java:89)
at freemarker.core.Expression.getStringValue(Expression.java:93)
at freemarker.core.DollarVariable.accept(DollarVariable.java:76)
at freemarker.core.Environment.visit(Environment.java:208)
at freemarker.core.MixedContent.accept(MixedContent.java:92)
at freemarker.core.Environment.visit(Environment.java:208)
at freemarker.core.Environment.process(Environment.java:188)
at freemarker.template.Template.process(Template.java:237)
at org.vfny.geoserver.wms.responses.featureInfo.FeatureTemplate.execute(FeatureTemplate.java:266)
... 67 more