Map code is added

src/MapInterface/CoustomHashMap/CoustomHashMap.java

+package MapInterface.CoustomHashMap;
+import java.util.*;
+public class CoustomHashMap
+{
+    HashMap<Integer,String> obj = new HashMap<>();
+
+    CoustomHashMap()
+    {
+        System.out.println("Coustom HaspMap object is created!");
+    }
+
+    void displayHashMap()
+    {
+
+        // add value in HashMap.
+        obj.put(1,"zain");
+        obj.put(2,"ali");
+        obj.put(3,"zain"); // value iss duplicate and key is unique it will add.
+        obj.put(1,"zain"); // this will not add because key isn't unique.
+
+        System.out.println("Values in Hash Map:"+obj);
+
+        // Searching in map.
+        if(obj.containsKey(2))
+        {
+            System.out.println("ali is in hash table as a record");
+        }
+
+
+        // get value
+
+        System.out.println("value of key 3 is:"+obj.get(3));
+
+
+
+
+    }
+}

src/MapInterface/CoustomHashMap/Main.java

+package MapInterface.CoustomHashMap;
+
+public class Main {
+    public static void main(String[] args) {
+
+    }
+}