question: merges 2 maps concode_field_sep PlaceHolder placeHolder concode_field_sep placeholderType placeHolder
target: ImmutableMap < K , V > function ( ImmutableMap < K , V > arg0 , ImmutableMap < K , V > arg1 ) { return ImmutableMap . < K , V > builder ( ) . putAll ( arg0 ) . putAll ( arg1 ) . build ( ) ; }