discovering Java programming

[juan_gandhi]

/**
 * A marker interface for classes that have no data inside
 * Meaning, two instances are equal if they have the same class
 */
public interface JustCode extends Serializable {
}
...
public interface Function<X, Y> extends JustCode {
  Y apply(X x);
}
...
public interface Function2<X, Y, Z> extends JustCode {
  Z apply(X x, Y y);
}
...
  
  public int hashCode(JustCode x) {
    return x == null ? 0 : x.getClass().hashCode();
  }

  public boolean equal(JustCode x, JustCode y) {
    return x == null ? y == null : y != null && x.getClass() == y.getClass();
  }

No shit, just discovered this kind of data.
You've probably noticed that I kind of prefer S to OOP. :)