[SCJP] HashSet e remove()

class KeyMaster {
	public int i;
	public KeyMaster(int i) { this.i = i; }
	public boolean equals(Object o) { return i == ((KeyMaster)o).i; }
	public int hashCode() { return i; }
}

public class Questao147 {

	public static void main(String[] args) {
		Set<KeyMaster> set = new HashSet<KeyMaster>();
		KeyMaster k1 = new KeyMaster(1);
		KeyMaster k2 = new KeyMaster(2);
		set.add(k1); set.add(k1);
		set.add(k2); set.add(k2);
		
		System.out.println(set.size() + ":");
		k2.i = 1;
		
		System.out.println(set.size() + ":");
		set.remove(k1);
		
		System.out.println(set.size() + ":");
		set.remove(k2);
		
		System.out.println(set.size());		
	}
}