HashMap values() Method in Java (original) (raw)

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 `

// 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 `

// 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.