Enum

[Prasad Maddipatla]

can you help out.

Program A:
enum cofeesize
{
BIG("8"),
HIGH("12"),
OVER("34")
{
public String getLid()
{
return "A";
}
};

private String ounces;

cofeesize(String ounces)
{
this.ounces = ounces;
}

public String getLid()
{
return "B";
}

}

public class Cofee
{
cofeesize size;


public static void main(String args[])
{
Cofee d = new Cofee();

d.size = cofeesize.BIG;

Cofee d1 = new Cofee();

d1.size = cofeesize.OVER;

System.out.println(d.size.getLid());

System.out.println(d1.size.getLid());

System.out.println(d1.size.ounces);
}
}

I get error when printing d1.size.ounces as onces is private and enum is outside the class Cofee.

Program B:

public class Cofee
{
cofeesize size;

enum cofeesize
{
BIG("8"),
HIGH("12"),
OVER("34")
{
public String getLid()
{
return "A";
}
};

private String ounces;

cofeesize(String ounces)
{
this.ounces = ounces;
}

public String getLid()
{
return "B";
}

}


public static void main(String args[])
{
Cofee d = new Cofee();

d.size = cofeesize.BIG;

Cofee d1 = new Cofee();

d1.size = cofeesize.OVER;

System.out.println(d.size.getLid());

System.out.println(d1.size.getLid());

System.out.println(d1.size.ounces);
}
}

Here i declared enum in the class cofee and get the output without any errors. I didnot understand as we consider enum as a class then a private instance variable can be acessable from outside enum?

[Kelvin Chenhao Lim]

Originally posted by Prasad Maddipatla:
I didnot understand as we consider enum as a class then a private instance variable can be acessable from outside enum?

Hi Prasad,

Private fields and methods are accessible anywhere within the top-level class enclosing them. This means that a private member in an inner class is accessible to the outer class, which is what happens in your second program.

More interestingly, this also means that different inner/nested classes of the same top-level class can access each other's private members. For example, you may be surprised to learn that this program is perfectly acceptable:

class Test {  
  class Foo {
    private class Fooz {
      private int secret = 42;
    }
  }
  
  static class Bar {
    Bar() {
      System.out.println(new Test().new Foo().new Fooz().secret);
    }
  }
  
  public static void main(String... args) {
    new Bar();    // prints "42"
  }
}

[Prasad Maddipatla]

Thank you Kelvin

[Shaili Merchant]

Hello..
I have jus started with preparing fro SCJP 1.5...
According to whatever I have understood from Chap 8 of K&B
Bar is a static nested class and it can be instantiated within static method as

Test.Bar b=new Test.Bar();

Please help me to solve this doubt

[Kelvin Chenhao Lim]

Hi "kssn nssk",

If you needed to use Bar outside of Test, then yes you'd need to include the outer class name as a prefix. However, since the above code uses Bar within Test itself, the prefix can be omitted. (But it's still fine to put it in.)

[Jesper de Jong]

"kssn nssk", please check your private messages. You can see them by clicking My Private Messages.

[Shaili Merchant]

Oh Thanks Kelvin...