Iterator in Generics

[Harikrishna Gorrepati]

Hi, Could you please let me know the differences between Line 9, 10, 11 and 12

import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Map.Entry;

public class Question45_Map0_Ask {
    public static void main(String[] args) {
	Map map = new HashMap();
	Iterator<Map.Entry<Integer, String>> i2 = map.entrySet().iterator();
	Iterator<Entry<Integer, String>> i3 = map.entrySet().iterator();
	Iterator<Map.Entry> i4 = map.entrySet().iterator();
    Iterator i5 = map.entrySet().iterator(); 
    }
}

[Wouter Oet]

What do you think the differences are?

[Harikrishna Gorrepati]

Here is my understanding.
1. iterator() method of Set interface returns Iterator interface.
API is : Iterator<E> iterator();
2. As per API, entrySet() returns Set<Map.Entry<K, V>>
API is : Set<Map.Entry<K, V>> entrySet();
My questions are

Difference between Map.Entry<Integer, String> and Entry<Integer, String> ?
Difference between Iterator<Entry<Integer, String>> and Iterator<Map.Entry> ?

Wouter Oet wrote:What do you think the differences are?

[Wouter Oet]

Harikrishna Gorrepati wrote:Difference between Map.Entry<Integer, String> and Entry<Integer, String>

There is no difference between Map.Entry<Integer, String> and Entry<Integer, String>. It's the same class. It is valid syntax because you imported Map.Entry.

Harikrishna Gorrepati wrote:Difference between Iterator<Entry<Integer, String>> and Iterator<Map.Entry> ?

Well the first iterators next method will return a Entry<Integer, String> and the second will return a Entry (non-generic).