How to iterate through a HashMap in Java
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In this tutorial, we are going to see how to iterate through a Hashmap in Java, using different methods:
- By using For loop
- By using While Loop with Iterator
Java Program to iterate through a HashMap using For loop
import java.util.*; public class Main { public static void main(String args[]) { HashMap<Integer, String> map = new HashMap<Integer, String>(); // add elements to HashMap map.put(1, "Alex"); map.put(2, "Emily"); map.put(3, "Thomas"); map.put(4, "Yohan"); //iterate through the HashMap using For loop for (Map.Entry m : map.entrySet()) { System.out.println("ID: "+m.getKey()+", Name: "+m.getValue()); } } }
Output:
ID: 1, Name: Alex ID: 2, Name: Emily ID: 3, Name: Thomas ID: 4, Name: Yohan
Java Program to iterate through a HashMap using While Loop with Iterator
import java.util.*; public class Main { public static void main(String args[]) { HashMap<Integer, String> map = new HashMap<Integer, String>(); // ajouter des éléments au HashMap map.put(1, "Alex"); map.put(2, "Emily"); map.put(3, "Thomas"); map.put(4, "Yohan"); //iterate through the HashMap using While loop + Iterator Iterator it = map.entrySet().iterator(); while (it.hasNext()) { Map.Entry m = (Map.Entry) it.next(); System.out.println("ID: "+m.getKey()+", Name: "+m.getValue()); } } }
Output:
ID: 1, Name: Alex ID: 2, Name: Emily ID: 3, Name: Thomas ID: 4, Name: YohanMCQPractice competitive and technical Multiple Choice Questions and Answers (MCQs) with simple and logical explanations to prepare for tests and interviews.Read More
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