| We can Iterate Map's key and values in lot of ways like getting keySet or by getting entrySet or by using Iterator interface. Lets see all these ways with simple example. | 
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
public class MapTest {
 public static void main(String[] args) {
  Map<String, String> map = new HashMap<String, String>();
  map.put("2", "two");
  map.put("3", "three");
  map.put("1", "one");
  map.put("4", "four");
  map.put("5", "five");
  
  System.out.println("Using entrySeT() ---- ");
  
                   for (Map.Entry<String, String> myMap : map.entrySet()) {
   System.out.println(myMap.getKey() + " : " + myMap.getValue());
  }
  
  System.out.println("\nUsing keySet() ---- ");
  
  for (Object myKey : map.keySet()) {
   System.out.println(myKey.toString() + " : " + map.get(myKey));
  }
  
  System.out.println("\nUsing Iterator interface ---- ");
  
  Iterator<?> itr = map.entrySet().iterator();
  while (itr.hasNext()) {
   Map.Entry myMap = (Map.Entry) itr.next();
   System.out.println(myMap.getKey() + " : " + myMap.getValue());
  }
 }
}
OUTPUT:
Using entrySeT() ---- 
2 : two
3 : three
1 : one
4 : four
5 : five
Using keySet() ---- 
2 : two
3 : three
1 : one
4 : four
5 : five
Using Iterator interface ---- 
2 : two
3 : three
1 : one
4 : four
5 : five
