HashMap values() Method in Java

Last Updated : 26 Nov, 2018

The java.util.HashMap.values() method of HashMap class in Java is used to create a collection out of the values of the map. It basically returns a Collection view of the values in the HashMap.

Syntax:

Hash_Map.values()

Parameters: The method does not accept any parameters.

Return Value: The method is used to return a collection view containing all the values of the map.

Below programs are used to illustrate the working of java.util.HashMap.values() Method:
Program 1: Mapping String Values to Integer Keys.

   // Java code to illustrate the values() method 
import java.util.*; 
  
public class Hash_Map_Demo { 
    public static void main(String[] args) 
    { 
  
        // Creating an empty HashMap 
        HashMap<Integer, String> hash_map = new HashMap<Integer, String>(); 
  
        // Mapping string values to int keys 
        hash_map.put(10, "Geeks"); 
        hash_map.put(15, "4"); 
        hash_map.put(20, "Geeks"); 
        hash_map.put(25, "Welcomes"); 
        hash_map.put(30, "You"); 
  
        // Displaying the HashMap 
        System.out.println("Initial Mappings are: " + hash_map); 
  
        // Using values() to get the set view of values 
        System.out.println("The collection is: " + hash_map.values()); 
    } 
} 
 
  

Output:

  Initial Mappings are: {20=Geeks, 25=Welcomes, 10=Geeks, 30=You, 15=4}  The collection is: [Geeks, Welcomes, Geeks, You, 4]

Program 2: Mapping Integer Values to String Keys.

   // Java code to illustrate the values() method 
import java.util.*; 
  
public class Hash_Map_Demo { 
    public static void main(String[] args) 
    { 
  
        // Creating an empty HashMap 
        HashMap<String, Integer> hash_map = new HashMap<String, Integer>(); 
  
        // Mapping int values to string keys 
        hash_map.put("Geeks", 10); 
        hash_map.put("4", 15); 
        hash_map.put("Geeks", 20); 
        hash_map.put("Welcomes", 25); 
        hash_map.put("You", 30); 
  
        // Displaying the HashMap 
        System.out.println("Initial Mappings are: " + hash_map); 
  
        // Using values() to get the set view of values 
        System.out.println("The collection is: " + hash_map.values()); 
    } 
} 
 
  

Output:

  Initial Mappings are: {4=15, Geeks=20, You=30, Welcomes=25}  The collection is: [15, 20, 30, 25]

Note: The same operation can be performed with any type of Mappings with variation and combination of different data types.

Java HashMap put() Method

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