question: static void checkInternalName ( final String name , final String msg ) { if ( name == null || name . length ( ) == 0 ) { throw new IllegalArgumentException ( "Invalid " + msg + " (must not be null or empty)" ) ; } if ( name . charAt ( 0 ) == '[' ) { checkDesc ( name , false ) ; } else { checkInternalName ( name , 0 , - 1 , msg ) ; } }
target:  Checks that the given string is a valid internal class name.