question: private String attr ( String name , Element element ) { String res = text ( element , "@" + name ) ; int i = name . indexOf ( ':' ) ; if ( res . length ( ) == 0 && i >= 0 ) { return attr ( name . substring ( i + 1 ) , element ) ; } return res ; }
target:  Extracts an attribute by name. Returns empty string if attribute was not found. If the attr name is prefixed and not found, an attempt is made to find it without prefix