PetBean.java

public class PetBean implements Serializable { 

 private List<Pet> pets; 

 private FilterAssembler filterAssembler; 

 public List<Pet> getFilteredPets() {
  return (List<Pet>) getFilterAssembler().filter(new ArrayList(pets)); 
 }

 public FilterAssembler<List<Pet>> getFilterAssembler() {
  if (filterAssembler == null) {
    filterAssembler = new FilterAssembler<List<Pet>>(Pet.class); 
  }
  return filterAssembler; 
 }

 // ... 

}