expand the environment variable in platform-agnostic syntax . the parameter expansion marker '' var '' will be replaced with real parameter expansion marker ' % ' for windows and ' $ ' for linux by nodemanager on container launch . for example : var will be replaced as $ var on linux , and % var % on windows . concode_field_sep String CONTAINER_TOKEN_FILE_ENV_NAME concode_elem_sep String PARAMETER_EXPANSION_RIGHT concode_elem_sep String variable concode_elem_sep String CLASS_PATH_SEPARATOR concode_elem_sep String APP_SUBMIT_TIME_ENV concode_elem_sep String STDOUT concode_elem_sep String LOG_DIR_EXPANSION_VAR concode_elem_sep String PARAMETER_EXPANSION_LEFT concode_elem_sep String MAX_APP_ATTEMPTS_ENV concode_elem_sep String APPLICATION_WEB_PROXY_BASE_ENV concode_elem_sep String STDERR concode_field_sep String $ concode_elem_sep String toString concode_elem_sep String key
String function ( ) { return PARAMETER_EXPANSION_LEFT + variable + PARAMETER_EXPANSION_RIGHT ; }