Different ways to Iterate through Map in Java

Learn different ways to iterate through Map object in Java.

Let’s create a Map

Map<String , String> fruits  = new HashMap<>();

fruits.put("apple" , "🍏" );

fruits.put("banana" , "🍌" );

fruits.put("grapes", " 🍇 ");

fruits.forEach(

    (k, v) -> System.out.println("Key : " + k + " value : " + v)

);

Set< Map.Entry<String, String> > entries = fruits.entrySet();

for(Map.Entry<String,String> entry : entries) {

   String key = entry.getKey();
   String value = entry.getValue();

   System.out.println(key + " <--> " + value);

Note : If we use for-each loop don’t forgot to check if the Map is not null ,otherwise it will throw NullPointerException .

To get keys of the Map

Set<String> keys = fruits.keySet();

for(String key : keys) {

 String value = fruits.get(key);

    System.out.println(key + " <--> " + value);

We can create iterator for entrySet of the map ,then use that to loop through each entry of the map.

Set<Map.Entry<String, String>> entries = fruits.entrySet();

Iterator<Map.Entry<String, String>> iterator = entries.iterator();

while (iterator.hasNext()){

   Map.Entry<String, String> entry = iterator.next();

   String key = entry.getKey();

   String value = entry.getValue();

   System.out.println(key + " <--> " + value);

If you only want keys you can get Keys by

Set<String> keys =fruits.keySet();

If you only want values of the map

Collection<String> values =  fruits.values();

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