Map isEmpty() Method in Java with Examples
Last Updated :
02 Jan, 2019
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
// Java code to show the implementation of
// isEmpty method in Map interface
import 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());
}
}
Program 2: Below is the code to show implementation of hashCode().
Java
// Java code to show the implementation of
// isEmpty method in Map interface
import 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