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.*;Â
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.*;Â
class MapSizeExample {Â
    // Main Method    public static void main(String[] args)    {Â
        Map<Integer, String> map            = new HashMap<Integer, String>();Â
        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
