+ Human, Specimen, Trait]
+
+ table_names = Hash[klasses.collect { |k| [k, k.table_name] }]
+
+ disabled_methods = Rails.configuration.disable_api_methods
+ avail_klasses = table_names.select{|k, t| !disabled_methods.include?(t+'.index')}
+ klasses = avail_klasses.keys
+
+ request_filters.each do |col, op, val|
+ if col.index('.') && !table_names.values.include?(col.split('.', 2)[0])
+ raise ArgumentError.new("Invalid attribute '#{col}' in filter")
+ end
+ end
+
+ wanted_klasses = []
+ request_filters.each do |col,op,val|
+ if op == 'is_a'
+ (val.is_a?(Array) ? val : [val]).each do |type|
+ type = type.split('#')[-1]
+ type[0] = type[0].capitalize
+ wanted_klasses << type
+ end
+ end
+ end
+
+ seen_last_class = false
+ klasses.each do |klass|
+ @offset = 0 if seen_last_class # reset offset for the new next type being processed
+
+ # if current klass is same as params['last_object_class'], mark that fact
+ seen_last_class = true if((params['count'].andand.==('none')) and
+ (params['last_object_class'].nil? or
+ params['last_object_class'].empty? or
+ params['last_object_class'] == klass.to_s))
+
+ # if klasses are specified, skip all other klass types
+ next if wanted_klasses.any? and !wanted_klasses.include?(klass.to_s)
+
+ # don't reprocess klass types that were already seen
+ next if params['count'] == 'none' and !seen_last_class
+
+ # don't process rest of object types if we already have needed number of objects
+ break if params['count'] == 'none' and all_objects.size >= limit_all
+