AbstractMap isEmpty() Method in Java with Examples

The AbstractMap.isEmpty() method of AbstractMap class is used to check for the emptiness of the map. The method returns True if no key-value pair or mapping is present in the map else False.

Syntax:

AbstractMap.isEmpty()

Parameters: The method does not take any parameters.

Return Value: The method returns boolean true if the map is empty or does not contain any mapping pairs else boolean false.

Below programs illustrates the working of AbstractMap.isEmpty() method:

Program 1: Mapping String Values to Integer Keys.

// Java code to illustrate the isEmpty() method

import java.util.*;

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

        // Creating an empty AbstractMap
        AbstractMap<String, Integer>
            abs_map = new HashMap<String, Integer>();

        // Mapping int values to string keys
        abs_map.put("Geeks", 10);
        abs_map.put("4", 15);
        abs_map.put("Geeks", 20);
        abs_map.put("Welcomes", 25);
        abs_map.put("You", 30);

        // Displaying the AbstractMap
        System.out.println("The Mappings are: "
                           + abs_map);

        // Checking for the emptiness of Map
        System.out.println("Is the map empty? "
                           + abs_map.isEmpty());
    }
}

Output:

The Mappings are: {4=15, Geeks=20, You=30, Welcomes=25}
Is the map empty? false

Program 2: For an empty HashMap

// Java code to illustrate the isEmpty() method

import java.util.*;

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

        // Creating an empty AbstractMap
        AbstractMap<String, Integer>
            abs_map = new HashMap<String, Integer>();

        // Displaying the AbstractMap
        System.out.println("The Mappings are: "
                           + abs_map);

        // Checking for the emptiness of Map
        System.out.println("Is the map empty? "
                           + abs_map.isEmpty());
    }
}

Output:

The Mappings are: {}
Is the map empty? true

Note: The same operation can be performed with any type of Mappings with variation and combination of different data types.