Review of three traversal methods of map

Map Three traversal methods of

import java.util.*;

/** *Map  Traverse  * Collection<V> values()  Returns the... Of the value contained in this map Collection aggregate . * Set<K> keySet()  Get all key, according to key obtain value * Set<Map.Entry<K,V>> entrySet() * K getKey()  Return the key corresponding to this entry . * V getValue() * */

public class MapOf_bianli {
    
    public static void main(String[] args) {
    
        Map<String,Integer> map1=new HashMap<>();
        map1.put(" Zhang Zetian ",25);
        map1.put(" Liu Yifei ",26);
        map1.put(" Faye Wong ",46);
        map1.put(" Nicholas Tse ",28);
        // Traversal methods 1.  Use  values() Method variable mapping ---> Collection<V> values()  Returns the... Of the value contained in this map Collection View .
        Collection<Integer> col=map1.values();
        for (Integer vals:col){
    
            System.out.println(vals);
        }
        // Traversal methods 2. Set<K> keySet()  Get all key, according to key obtain value
        Set<String> set=map1.keySet();
        // To obtain a set aggregate , Use enhancements foreach and  Iterator
        Iterator it=set.iterator();// Get one Iterator object 
        while(it.hasNext()){
    
            System.out.println(map1.get(it.next()));
        }
    /** Traversal methods 3. Set<Map.Entry<K,V>> entrySet() K getKey()  Return the key corresponding to this entry . V getValue() */
    Set<Map.Entry<String,Integer>> entries=map1.entrySet();
    // call map A collection of entrySet() Method returns Set aggregate , The type is Map.Entry<String,Integer>
     for (Map.Entry<String,Integer> ent:entries){
    // Use enhancements for Loop through each pair of key value pair elements 
         System.out.println(ent.getKey()+"----->"+ent.getValue());
     }

    }

}