RE: Cost of instantiating

Didn't happen on mine, Paul:

public class Immutable {

   public static void main(String[] args) {
      
      int int1 = 0;
      Integer i1 = new Integer(0);
      Integer i2 = new Integer(0);
      Integer i3 = new Integer(int1);
      
      boolean eq1_2 = (i1 == i2);
      boolean eq1_3 = (i1 == i3);
      boolean eq2_3 = (i2 == i3);
      boolean equal1_2 = (i1.equals(i2));
      boolean equal1_3 = (i1.equals(i3));
      boolean equal2_3 = (i2.equals(i3));
      
      System.out.println("" + eq1_2 + ' ' + eq1_3 + ' ' + eq2_3);
      System.out.println("" + equal1_2 + ' ' + equal1_3 + ' ' +
equal2_3);
      
      System.exit(0);
   }
}

Prints out:

false false false
true true true

Joe

> From: Paul Morgan
> 
> JVMs will cache immutable objects.  Even though you've called
> 
> new Integer(0)
> 
> five times you've only created one Integer object which gets
referenced
> five
> times.  You can confirm this by comparing Total1 = Total2.  After
being
> initialized they should be equal (pointing to the same Integer(0)
object).