code: public String getResourceType(CmsFileInfo file) {
  
          String typeName = null;
          typeName = getExtensionMapping().get(file.getFileSuffix().toLowerCase());
          if (typeName == null) {
              typeName = "plain";
          }
          return typeName;
      }
docs: Returns the resource type name for a given filename.<p>
  
  @param file the file info
  
  @return the resource type name