Syntax error How can we iterate the elements of List and Map using lambda expression in Java?

How can we iterate the elements of List and Map using lambda expression in Java?

The lambda expressions are inline code that implements a functional interface without creating an anonymous class. In Java 8, forEach statement can be used along with lambda expression that reduces the looping through a Map to a single statement and also iterates over the elements of a list. The forEach() method defined in an Iterable interface and accepts lambda expression as a parameter.

Example ( List using Lambda Expression)

import java.util.*;

public class ListIterateLambdaTest {
   public static void main(String[] argv) {
      List<String> countryNames = new ArrayList<String>();
      countryNames.add("India");
      countryNames.add("England");
      countryNames.add("Australia");
      countryNames.add("Newzealand");
      countryNames.add("South Africa");

      // Iterating country names through forEach using Lambda Expression
      countryNames.forEach(name -> System.out.println(name));
   }
}

Output

India
England
Australia
Newzealand
South Africa


Example (Map using Lambda Expression)

import java.util.*;

public class MapIterateLambdaTest {
   public static void main(String[] args) {
      Map<String, Integer> ranks = new HashMap<String, Integer>();
      ranks.put("India", 1);
      ranks.put("Australia", 2);
      ranks.put("England", 3);
      ranks.put("Newzealand", 4);
      ranks.put("South Africa", 5);
      // Iterating through      
      forEach using Lambda Expression
      ranks.forEach((k,v) -> System.out.println("Team : " + k + ", Rank : " + v));
   }
}

Output

Team : Newzealand, Rank : 4
Team : England, Rank : 3
Team : South Africa, Rank : 5
Team : Australia, Rank : 2
Team : India, Rank : 1
Updated on: 2020-07-11T06:15:14+05:30

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