I tried searching around the site, but there is way too many threads with keywords interator or implementation. So, in a nut shell, what is the difference between various standard iterator implementations? I have not noticed anything different, besides the fact that .getClass() returns different strings.
List myList = (List) Arrays.asList("a", "b", "c", "d");
Set hashSet = new HashSet<String>();
Set treeSet = new TreeSet<String>();
ArrayList arrayList = new ArrayList<String>();
System.out.println(arrayList.iterator().getClass());//ArrayList
System.out.println(hashSet.iterator().getClass());//HashSet
System.out.println(myList.iterator().getClass());//List produced by Arrays.asList()
System.out.println(treeSet.iterator().getClass());//TreeSet
Result is as follows:
class java.util.ArrayList$Itr
class java.util.HashMap$KeyIterator
class java.util.AbstractList$Itr
class java.util.TreeMap$KeyIterator
So, why not keep the interface for people to implement in custom classes if needed, and have one concrete implementation across all Collections?
