This method is used to check if a map is having any entry for key and value pairs. If no mapping exists, then this returns true.
Syntax:
boolean isEmpty()
Parameters: This method has no argument.
Returns: This method returns True if the map does not contain any key-value mapping.
Below programs show the implementation of int isEmpty() method.
Program 1:
// Java code to show the implementation of// isEmpty method in Map interfaceimport java.util.*;public class GfG { // Driver code public static void main(String[] args) { // Initializing a Map of type HashMap Map<String, String> map = new HashMap<>(); System.out.println(map); System.out.println(map.isEmpty()); }} |
Output:
{}
true
Program 2: Below is the code to show implementation of hashCode().
// Java code to show the implementation of// isEmpty method in Map interfaceimport java.util.*;public class GfG { // Driver code public static void main(String[] args) { // Initializing a Map of type HashMap Map<String, String> map = new HashMap<>(); map.put("1", "One"); map.put("3", "Three"); map.put("5", "Five"); map.put("7", "Seven"); map.put("9", "Ninde"); System.out.println(map); System.out.println(map.isEmpty()); }} |
Output:
{1=One, 3=Three, 5=Five, 7=Seven, 9=Ninde}
false
Reference:
Oracle Docs
