Map hashCode() Method in Java with Examples

This method is used to generate a hashCode for the given map containing key and values.

Syntax:

int hashCode()

Parameters: This method has no argument.

Returns: This method returns the hashCode value for the given map.

Below programs show the implementation of int hashCode() method.

Program 1:

// Java code to show the implementation of
// hashCode 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<Integer, 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);

        int hash = map.hashCode();

        System.out.println(hash);
    }
}

Output:

{1=One, 3=Three, 5=Five, 7=Seven, 9=Ninde}
238105666

Program 2: Below is the code to show implementation of hashCode().

// Java code to show the implementation of
// hashCode 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);

        int hash = map.hashCode();

        System.out.println(hash);
    }
}

Output:

{1=One, 3=Three, 5=Five, 7=Seven, 9=Ninde}
238105618

Reference:
Oracle Docs