enum EmpComp {
	BY_ID, BY_NAME, BY_AGE;
}

class CompareEmploye implements Comparator<Employe> {
	private EmpComp ec;

	public CompareEmploye(EmpComp ec) {
		this.ec = ec;
	}

	@Override
	public int compare(Employe e1, Employe e2) {
		// TODO Auto-generated method stub
		switch (ec) {
		case BY_ID:
			return e2.getId() - e1.getAge();
		case BY_NAME:
			return e2.getName().compareTo(e1.getName());
		case BY_AGE:
			return e2.getAge() - e1.getAge();
		}
		return 0;
	}

}

class Employe {
	private int id;
	private String name;
	private int age;

	public Employe(int id, String name, int age) {
		this.id = id;
		this.name = name;
		this.age = age;
	}

main {
		CompareEmploye come = new CompareEmploye(EmpComp.BY_ID);
		List<Employe> list = new ArrayList() {
			{
				add(new Employe(1, "John", 25));
				add(new Employe(2, "Smith", 55));
				add(new Employe(7, "Rose", 45));
				add(new Employe(5, "Byrne", 33));
			}
		};
		System.out.println(list);
		Collections.sort(list,come);
		System.out.println(list);
}