Re: Hash table performance

I'm having trouble getting Java's hash tables to run as fast as .NET's.
Specifically, the following program is 32x slower than the equivalent
on .NET:

  import java.util.Hashtable;
  
  public class Hashtbl {
    public static void main(String args[]){
      Hashtable hashtable = new Hashtable();
  
      for(int i=1; i<=10000000; ++i) {
        double x = i;
        hashtable.put(x, 1.0 / x);
      }
  
      System.out.println("hashtable(100.0) = " + hashtable.get(100.0));
    }
  }

My guess is that this is because the JVM is boxing every floating point
number individually in the hash table due to type erasure whereas .NET
creates a specialized data structure specifically for a float->float hash
table with the floats unboxed. Consequently, the JVM is doing enormously
numbers of allocations whereas .NET is not.

Is that correct?