I wonder why would anybody want to use identity comparison for fields in equals, like here (Java syntax):class C {    private A a;    public boolean equals(Object other) {        // standard boring prelude        if (other==this) return true;        if (other==null) return false;        if (other.getClass() != this.getClass()) return false;        C c = (C) other;        // the relevant part        if (c.a != this.a) return false;        // more tests... and then        return true;    }    // getter, setters, hashCode, ...}Using == is a bit faster than equals and a bit shorter (due to no need for null tests), too, but in what cases (if any) you'd say it's really better to use == for fields inside equals?
When to use identity comparison instead of equals?
object oriented;comparison