Map size() method in Java is used to get the total number entries i.e, key-value pair. So this method is useful when you want total entries present on the map. If the map contains more than Integer.MAX_VALUE elements returnInteger.MAX_VALUE
Syntax:
int size();
Parameter: This method does not take any parameter.
Return value: This method returns the number of key-value mappings in this map.
Example 1: For non-generic input
Java
// Java program to illustrate// the Map size() Methodimport java.util.*;public class MapSizeExample { // Main Method public static void main(String[] args) { Map map = new HashMap(); // Adding key-values map.put(1, "Amit"); map.put(5, "Rahul"); map.put(2, "Jai"); map.put(6, "Amit"); // using the method System.out.println("Size of the map is : " + map.size()); }} |
Output:
Size of the map is : 4
Example 2: For Generic Input
Java
// Java program to illustrate// the Map size() Methodimport java.util.*;class MapSizeExample { // Main Method public static void main(String[] args) { Map<Integer, String> map = new HashMap<Integer, String>(); map.put(1, "one"); map.put(2, "two"); map.put(3, "three"); map.put(4, "four"); // using the method System.out.println("Size of map is :" + map.size()); }} |
Output:
Size of the map is : 4
