question: private void formatNodeTo ( Formatter f , int level , RadixTreeNode < T > node ) { for ( int i = 0 ; i < level ; i ++ ) { f . format ( " " ) ; } f . format ( "|" ) ; for ( int i = 0 ; i < level ; i ++ ) { f . format ( "-" ) ; } if ( node . isReal ( ) == true ) f . format ( "%s[%s]*%n" , node . getKey ( ) , node . getValue ( ) ) ; else f . format ( "%s%n" , node . getKey ( ) ) ; for ( RadixTreeNode < T > child : node . getChildern ( ) ) { formatNodeTo ( f , level + 1 , child ) ; } }
target:  WARNING! Do not use this for a large Trie, it's for testing purpose only.