Example of a Static Factory Method, for the this article https://medium.com/@thomaspoignant/static-factory-methods-59e88d2d737f#.9sxp2fho6

RandomLongGenerator.java

public class RandomLongGenerator {
  private final long min;
  private final long max;
  private RandomIntGenerator(long min, long max) {
    this.min = min;
    this.max = max;
  }
  public static RandomLongGenerator between(long max, long min) {
    return new RandomLongGenerator(min, max);
  }
public static RandomLongGenerator biggerThan(long min) {
    return new RandomLongGenerator(min, Long.MAX_VALUE);
  }
  public static RandomLongGenerator smallerThan(int max) {
    return new RandomLongGenerator(Long.MIN_VALUE, max);
  }
  public int next() {...}
}