EnumMap Class in Java

EnumMap keySet() Method in Java

Last Updated : 13 Jul, 2018

The Java.util.EnumMap.keySet() method in Java is used to return the set view of the keys contained in the map. Syntax:

Enum_Map.keySet()

Parameters: The method does not accept any argument. Return Value: The method returns the set view of the keys contained in the map. Below programs illustrate the keySet() function: Program 1:

Java

// Java program to demonstrate keySet()
import java.util.*;

// An enum of geeksforgeeks
public enum gfg {
    India,
    United_States,
    China
};

class Enum_demo {
    public static void main(String[] args)
    {

        EnumMap<gfg, String> mp = new 
                    EnumMap<gfg, String>(gfg.class);

        // Values are associated
        mp.put(gfg.India, "61.7%");
        mp.put(gfg.United_States, "18.2%");
        mp.put(gfg.China, "2.5%");

        // Prints the map
        System.out.println("Mappings: " + mp);

        // Store the set view of the key
        Set<gfg> set_view = mp.keySet();

        // Print the result
        System.out.println("Set view of the key: " + 
                                            set_view);
    }
}

Output:

Mappings: {India=61.7%, United_States=18.2%, China=2.5%}
Set view of the key: [India, United_States, China]

Program 2:

Java

// Java program to demonstrate keySet()
import java.util.*;

// An enum of geeksforgeeks
public enum gfg {
    Global_today,
    India_today
};

class Enum_demo {
    public static void main(String[] args)
    {

        EnumMap<gfg, Integer> mp = 
                new EnumMap<gfg, Integer>(gfg.class);

        // Values are associated
        mp.put(gfg.Global_today, 799);
        mp.put(gfg.India_today, 69);

        // Prints the map
        System.out.println("Mappings: " + mp);

        // Store the set view of the key
        Set<gfg> set_view = mp.keySet();

        // Print the result
        System.out.println("Set view of the key: " +
                                             set_view);
    }
}

Output:

Mappings: {Global_today=799, India_today=69}
Set view of the key: [Global_today, India_today]

EnumMap Class in Java

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