method to return the singleton instance of this class concode_field_sep int SLIDE_PRELOAD_COUNT concode_elem_sep String CHAT_LOG_EXTENSION concode_elem_sep Log log concode_elem_sep PresentationManager singleton concode_elem_sep Map presentationMap concode_field_sep Presentation createPresentation concode_elem_sep Presentation[] getPresentationList concode_elem_sep boolean passwordExists concode_elem_sep Object removePresentation concode_elem_sep Map getPresentationMap concode_elem_sep boolean isPasswordAndPresentationMatch concode_elem_sep void joinPresentation concode_elem_sep boolean presentationExists concode_elem_sep Presentation getPresentation
PresentationManager function ( ) { if ( singleton == null ) { singleton = new PresentationManager ( ) ; } return ( singleton ) ; }