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.
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