Q of Dan's Mock Exam

[Claire Yang]

Hi, I modified one of Dan's Mock Exam questions to let it run completely. My question is why it prints "2513469" since the code doesn't call the constructor R that includes an int parameter?

class P {void m1() throws Exception {}}
class Q {
  {System.out.print("1");}
  static {System.out.print("2");}
  Q() {System.out.print("3");}
}
class R extends Q {
  {System.out.print("4"); new P().m1();}
  static {System.out.print("5");}
  R() throws Exception {} {System.out.print("6");}
  R(int i)throws Exception {} {System.out.print("9");}
}
class S {
  public static void main(String[] args) {
    try { new R(); }
    catch(Exception e) { System.out.print("Got you!"); }
  }
}

Thanks in advance.
PS. How to use FONT tag to let the code be showed bigger? I tried but failed.
[ October 28, 2002: Message edited by: Claire Yang ]

[Ron Newman]

In this code:

R(int i)throws Exception {} {System.out.print("9");}

the body of the constructor is {} -- that is, empty. The System.out.print("9"); statement is not part of the constructor. It is an instance initializer and will always run.

[Jay Ashar]

If it is an instance initializer shouldnt it run before constructor runs??

[Jessica Sant]

Originally posted by Claire Yang:

PS. How to use FONT tag to let the code be showed bigger? I tried but failed.

can't be done -- HTML has been disabled in this forum. The [code] blocks come in one font only. sorry!

[Ron Newman]

It does run before your constructor does (but not before the superclass constructor does).
Note that your constructor body is also {} -- it prints out nothing. {System.out.print("6");} is another instance initializer.
[ October 29, 2002: Message edited by: Ron Newman ]

[Claire Yang]

Hi, thank a lot. I know where I was wrong now, I should put the println statement into the block of the constructor. Sorry, a "mistaken" question!