question: private void createMapWhenNeeded ( ) { if ( isMapInitialized ) { return ; } if ( resourceBundle != null ) { Set < String > set = resourceBundle . keySet ( ) ; topLevelMap = new HashMap < String , Object > ( set . size ( ) ) ; for ( String key : set ) { Object value = resourceBundle . getObject ( key ) ; topLevelMap . put ( key , value ) ; } } else { topLevelMap = new HashMap < String , Object > ( 1 ) ; } topLevelMap . put ( "_RESOURCE_BUNDLE_" , resourceBundle ) ; isMapInitialized = true ; }
target:  Creates the topLevelMap only when it is required