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 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());
}
} |
Output:
{} true
Program 2: Below is the code to show implementation of hashCode().
// 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