The java.util.WeakHashMap.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 Map.
Syntax:
Weak_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.WeakHashMap.values() Method:
Program 1:
// Java code to illustrate the values() method import java.util.*;
public class Weak_Hash_Map_Demo {
public static void main(String[] args)
{
// Creating an empty WeakHashMap
Map<Integer, String> weak_hash = new WeakHashMap<Integer, String>();
// Mapping string values to int keys
weak_hash.put( 10 , "Geeks" );
weak_hash.put( 15 , "4" );
weak_hash.put( 20 , "Geeks" );
weak_hash.put( 25 , "Welcomes" );
weak_hash.put( 30 , "You" );
// Displaying the WeakHashMap
System.out.println( "Initial Mappings are: " +
weak_hash);
// Using values() to get the set view of values
System.out.println( "The collection is: " +
weak_hash.values());
}
} |
Initial Mappings are: {30=You, 15=4, 10=Geeks, 25=Welcomes, 20=Geeks} The collection is: [You, 4, Geeks, Welcomes, Geeks]
Program 2:
// Java code to illustrate the values() method import java.util.*;
public class Weak_Hash_Map_Demo {
public static void main(String[] args)
{
// Creating an empty WeakHashMap
Map<String, Integer> weak_hash = new WeakHashMap<String, Integer>();
// Mapping int values to string keys
weak_hash.put( "Geeks" , 10 );
weak_hash.put( "4" , 15 );
weak_hash.put( "Geeks" , 20 );
weak_hash.put( "Welcomes" , 25 );
weak_hash.put( "You" , 30 );
// Displaying the WeakHashMap
System.out.println( "Initial Mappings are: " +
weak_hash);
// Using values() to get the set view of values
System.out.println( "The collection is: " +
weak_hash.values());
}
} |
Initial Mappings are: {Welcomes=25, 4=15, You=30, Geeks=20} The collection is: [25, 15, 30, 20]
Note: The same operation can be performed with any type of Mappings with variation and combination of different data types.