This is my first geoserver project in which Im trying to visualise osm.xml data from Openstreetmap which is converted to Postgis spatial data format in Postgresql using converter tool osm2pgsql . This data was then imported into Geoserver and styling SLD was applied which is obtained from the above mentioned URLs.
There is no problem in syntax and no validation errors but while rendering the map there is runtime error which is resulting in white tiles . This occurs an soon as I try to add an attritube to classify the available data i.e for example osm_roads as primary secondary and tertiary roads
*Error *is : ERROR [geoserver.ows] -
org.geoserver.platform.ServiceException: Rendering process failed
Cause is : Caused by: java.lang.ClassCastException: java.util.ArrayList cannot be cast to org.opengis.feature.type.AttributeDescriptor
Windows 7 Geoserver 2.8.0 Java jre1.8.0_60/jde1.8.0_60 Postgresql 9.4 http://download.geofabrik.de/europe/germany/berlin.html http://docs.geoserver.org/latest/en/user/_downloads/line_attributebasedline.sld