map interation in java

Map map = new HashMap();
Iterator entries = map.entrySet().iterator();
while (entries.hasNext()) {
    Map.Entry entry = (Map.Entry) entries.next();
    Integer key = (Integer)entry.getKey();
    Integer value = (Integer)entry.getValue();
    System.out.println("Key = " + key + ", Value = " + value);
}

Map<Integer, Integer> map = new HashMap<Integer, Integer>();

// Iterating over keys only
for (Integer key : map.keySet()) {
    System.out.println("Key = " + key);
}

// Iterating over values only
for (Integer value : map.values()) {
    System.out.println("Value = " + value);
}

// Java program to demonstrate iteration over  
// Map using keySet() and values() methods 
  
import java.util.Map; 
import java.util.HashMap; 
  
class IterationDemo  
{ 
    public static void main(String[] arg) 
    { 
        Map<String,String> gfg = new HashMap<String,String>(); 
      
        // enter name/url pair 
        gfg.put("GFG", "geeksforgeeks.org"); 
        gfg.put("Practice", "practice.geeksforgeeks.org"); 
        gfg.put("Code", "code.geeksforgeeks.org"); 
        gfg.put("Quiz", "quiz.geeksforgeeks.org"); 
          
        // using keySet() for iteration over keys 
        for (String name : gfg.keySet())  
            System.out.println("key: " + name); 
          
        // using values() for iteration over keys 
        for (String url : gfg.values())  
            System.out.println("value: " + url); 
    } 
} 

// Java program to demonstrate iteration over  
// Map.entrySet() entries using for-each loop 
  
import java.util.Map; 
import java.util.HashMap; 
  
class IterationDemo  
{ 
    public static void main(String[] arg) 
    { 
        Map<String,String> gfg = new HashMap<String,String>(); 
      
        // enter name/url pair 
        gfg.put("GFG", "geeksforgeeks.org"); 
        gfg.put("Practice", "practice.geeksforgeeks.org"); 
        gfg.put("Code", "code.geeksforgeeks.org"); 
        gfg.put("Quiz", "quiz.geeksforgeeks.org"); 
          
        // using for-each loop for iteration over Map.entrySet() 
        for (Map.Entry<String,String> entry : gfg.entrySet())  
            System.out.println("Key = " + entry.getKey() + 
                             ", Value = " + entry.getValue()); 
    } 
} 

Map<Integer, Integer> map = new HashMap<Integer, Integer>();
for (Map.Entry<Integer, Integer> entry : map.entrySet()) {
    System.out.println("Key = " + entry.getKey() + ", Value = " + entry.getValue());
}