please tell me what z will print and why. thanks

public class X protected String a; public X(String a) l this . a = a; addWarning ); public void addWarning) I if (a.length ( ) > 3) a = a + ": long string !" public void reset (Object o) ?- "object (" + o.toString () + ")"; public String toString ) I return a; public class Y extends XI public Y(String a) l super (a); public void addWarning) I if (?.length ( )