Question: I'm using Susy 2 with breakpoint-sass to create my media queries.

It's outputting like:

```
@media (min-width: 1000px)

```

I'm wondering why the screen is missing? It should read:

```
@media screen (min-width: 1000px)

```

I'm trying to add css3-mediaqueries-js which isn't working and I think that might be why.

Answer: 
If you want to use `HashSet`, you can override `hashCode` and `equals` to exclusively look at those two members.

Hash code: (`31` is just a prime popularly used for hashing in Java)

```
return 31*id_a + id_b;

```

Equals: (to which you'll obviously need to add `instanceof` checks and type conversion)

```
return id_a == other.id_a && id_b == other.id_b;

```

If you don't want to bind these functions to the class because it's used differently elsewhere, but you still want to use `HashSet`, you could consider:

* Creating an intermediate class to be stored in the set, which will contain your class as a member and implement the above methods appropriately.
* Use your string approach
* Use `HashSet<Point>` - `Point` is not ideal for non-coordinate purposes as the members are simply named `x` and `y`, but I do find it useful to have such a class available, at least for non-production code.

---

Alternatively, if you want to use `TreeSet`, you could have your class implement `Comparable` (overriding `compareTo`) or provide a `Comparator` for the `TreeSet`, both of which would compare primarily on the one id, and secondarily on the other.

The basic idea would look something like this:

```
if (objectA.id_a != objectB.id_a)
  return Integer.compare(objectA.id_a, objectB.id_a);
return Integer.compare(objectA.id_b, objectB.id_b);

```
See this, Here I override the equals() and hashcode() to ensure uniqueness on "name" field of a Person object

```
public class SetObjectEquals {
    Person p1 = new Person("harley");
    Person p2 = new Person("harley");

    public void method1() {
        Set<Person> set = new HashSet<Person>();
        set.add(p1);
        set.add(p2);
        System.out.println(set);
    }

    public static void main(String[] args) {
        SetObjectEquals obj = new SetObjectEquals();
        obj.method1();
    }

}

class Person {
    String name;

    @Override
    public int hashCode() {
        final int prime = 31;
        int result = 1;
        result = prime * result + ((name == null) ? 0 : name.hashCode());
        return result;
    }

    @Override
    public boolean equals(Object obj) {
        if (this == obj)
            return true;
        if (obj == null)
            return false;
        if (getClass() != obj.getClass())
            return false;
        Person other = (Person) obj;
        if (name == null) {
            if (other.name != null)
                return false;
        } else if (!name.equals(other.name))
            return false;
        return true;
    }

    Person(String name) {
        this.name = name;
    }
}

```