Fibonacci in Java

Fib.java

import java.util.*;

public class Fib {
    Map<Integer,Long> memo;

    public Fib() {
        memo = new HashMap<Integer,Long>();
        memo.put(0,0L);
        memo.put(1,1L);
    }

    public Long get(int n) {
        if (memo.get(n) != null) {
            return memo.get(n);
        } else {
            Long result = get(n-1) + get(n-2);
            memo.put(n,result);
            return  result;
        }
    }

    public static void main(String[] args) {
        for (int i=0 ; i<50 ; i++) {
            System.out.println(new Fib().get(i));
        }
    }
}