question: checks whether the string contains only digit characters . null and empty string will return false . concode_field_sep PlaceHolder placeHolder concode_field_sep boolean isNumber
target: boolean function ( final String arg0 ) { if ( StringUtils . isEmpty ( arg0 ) ) { return false ; } for ( int loc0 = 0 ; loc0 < arg0 . length ( ) ; loc0 ++ ) { if ( ! Character . isDigit ( arg0 . charAt ( loc0 ) ) ) { return false ; } } return true ; }