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Java Program to find keys from a Linked HashMap and store it in a list
Let us first create a LinkedHashMap with key-value pair −
Map<String, String>map = new LinkedHashMap<String, String>();
map.put("1", "Katie");
map.put("2", "Peter");
map.put("3", "Amy");
map.put("4", "Kane");
map.put("5", "Colin");
map.put("6", "Andre");
map.put("7", "Pollard");
map.put("8", "David");
map.put("9", "Jofra");
map.put("10", "Akila");Now, create a new List and store the keys in it for the above Map −
List<String>list = new ArrayList<String>(); list.addAll(map.keySet());
Example
import java.util.ArrayList;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
public class Demo {
public static void main(String[] args) {
Map<String, String>map = new LinkedHashMap<String, String>();
map.put("1", "Katie");
map.put("2", "Peter");
map.put("3", "Amy");
map.put("4", "Kane");
map.put("5", "Colin");
map.put("6", "Andre");
map.put("7", "Pollard");
map.put("8", "David");
map.put("9", "Jofra");
map.put("10", "Akila");
List<String>list = new ArrayList<String>();
list.addAll(map.keySet());
System.out.println("Keys...");
for (String str: list) {
System.out.println(str);
}
}
}Output
Keys... 1 2 3 4 5 6 7 8 9 10
Updated on: 30-Jul-2019
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