How to Convert Map into List Using Java 8 ?

In this article we will see how to convert Map into List using Java 8 ? While working with Java applications you might come up with a situation where you want to convert Map into List.

Here in our example we will convert Map<Integer, String> into List<Integer> and List<String>. So basically we will get two lists out of this Map. One for keys and other is for values.

Below is the example.

import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;

public class MapToList {

	public static void main(String[] args) {
		Map<Integer, String> map = new HashMap<>();
		
		map.put(1, "John");
		map.put(2, "Raj");
		map.put(3, "Tom");
		
		List<Integer> intValues = map.keySet().stream().collect(Collectors.toList());
		System.out.println(intValues);
		
		List<String> strValues = map.values().stream().collect(Collectors.toList());
		System.out.println(strValues);
		
	}

}

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