Fib class in Java

fibonacci2.java

import java.util.List;
import java.util.stream.Stream;
import java.util.stream.Collectors;
import java.util.function.Supplier;
import java.math.BigInteger;

class Fibonacci {
  private static Stream<BigInteger> getGenerator() {
    return Stream.generate(new Supplier<BigInteger>() {
      private BigInteger a = BigInteger.ZERO;
      private BigInteger b = BigInteger.ONE;
      @Override public BigInteger get() {
        BigInteger t = a;
        a = b;
        b = b.add(t);
        return a;
      }
    });
  }
  public static Stream<BigInteger> generate() {
    return getGenerator();
  }
  public static List<BigInteger> generate(int n) {
    return getGenerator().limit(n).collect(Collectors.toList());
  }
  public static BigInteger nth(int n) {
    return getGenerator().limit(n).reduce((a, b) -> b).get();
  }
}

class Main {
  public static void main(String[] args) {
    System.out.println(Fibonacci.generate(50));
    Fibonacci.generate().limit(50).forEach(System.out::println);
    System.out.println(Fibonacci.nth(50));
  }
}