question: public final String toString ( ) { StringBuffer buffer = new StringBuffer ( ) ; int p = buffer . length ( ) ; try { appendDebugString ( buffer ) ; } catch ( RuntimeException e ) { buffer . setLength ( p ) ; buffer . append ( "!" ) ; buffer . append ( standardToString ( ) ) ; } return buffer . toString ( ) ; }
target:  Returns a string representation of this node suitable for debugging purposes only.