The values() method of ConcurrentHashMap 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 ConcurrentHashMap.
Syntax:
ConcurrentHashMap.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 ConcurrentHashMap.values() Method:
Program 1: Mapping String Values to Integer Keys.
// Java code to illustrate the values() method import java.util.*;
import java.util.concurrent.*;
public class ConcurrentHashMapDemo {
public static void main(String[] args)
{
// Creating an empty ConcurrentHashMap
ConcurrentHashMap<Integer, String> hash_map
= new ConcurrentHashMap<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 keySet() to get the set view of keys
System.out.println( "The Collection is: "
+ hash_map.values());
}
} |
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.*;
import java.util.concurrent.*;
public class ConcurrentHashMapDemo {
public static void main(String[] args)
{
// Creating an empty ConcurrentHashMap
ConcurrentHashMap<String, Integer>
hash_map = new ConcurrentHashMap<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 keySet() to get the set view of keys
System.out.println( "The Collection is: "
+ hash_map.values());
}
} |
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.