Subset of collection

Question

Is it possible to accomplish the following without unchecked casts warnings? I want to be able to extract a subset of a collection (based on class) and return the appropriate type. For example I have a collection of Animals and I want to return a collection of Lions from it. See sample code below:
class Animal {}
class Lion extends Animal {}
class Monkey extends Animal {}
class Zoo {
   Collection<Animal> animals;
   public Zoo() {
      animals = new HashSet<Animal>();
   public <T extends Animal> Collection<T> getAnimals(Class<T> clazz) {
      Collection<T> temp = new HashSet<T>();
      for (Animal animal : animals) {
         if (animal.getClass().equals(clazz)) {
            temp.add((T)animal); // Here is the problem (unchecked warning)
      return temp;
   public void addAnimal(Animal animal) {
      animals.add(animal);
   public static void main(String[] args) {
      Zoo zoo = new Zoo();
      zoo.addAnimal(new Lion());
      zoo.addAnimal(new Lion());
      zoo.addAnimal(new Monkey());
      Collection<Lion> lions = zoo.getAnimals(Lion.class);
      for (Lion lion : lions) System.out.println(lion);//works (all lions)
}

Answer 1

Call me old fashioned, but how is the Zoo class above any conceivable advance upon the below??
public class Zoo {
      Collection animals = new HashSet();  
      public Zoo() { }
      public Collection getAnimals(Class clazz) {     
           Collection temp = new HashSet();     
           for (Iterator iter = this.animals.iterator(); iter.hasNext(); ) {
                Animal animal = (Animal)iter.next();// Here is the problem (unchecked warning)
                if (animal.getClass().equals(clazz)) {           
                     temp.add(animal);        
           return temp;  
      public void addAnimal(Animal animal) {     
           this.animals.add(animal);  
      public static void main(String[] args) {     
           Zoo zoo = new Zoo();     
           zoo.addAnimal(new Lion());     
           zoo.addAnimal(new Lion());     
           zoo.addAnimal(new Monkey());     
           Collection lions = zoo.getAnimals(Lion.class);     
           for (Iterator iter = lions.iterator(); iter.hasNext(); )  {
                System.out.println(iter.next()); //works (all lions)  
}...and I bet you read this snippet twice as fast as the OP.
/k1