Create hashmap in java

Design a HashMap without using any built-in hash table libraries. To be specific, your design should include these functions:

• put(key, value): Insert a (key, value) pair into the HashMap.

  If the value already exists in the HashMap, update the value.

• get(key): Returns the value to which the specified key is mapped, or -1 if this map contains no mapping for the key.
• remove(key): Remove the mapping for the value key if this map contains the mapping for the key.

Examples:

Input: n = 8

• put(1, 1) 
• put(2, 2)
• get(1) 
• get(3)
• put(2, 1) 
• get(2)
• remove(2)
• get(2)

Output: 
1
-1
1
-1

Explanation: MyHashMap hashMap = new MyHashMap();
hashMap.put(1, 1);          
hashMap.put(2, 2);         
hashMap.get(1); // returns 1
hashMap.get(3); // returns -1 (not found)
hashMap.put(2, 1); // update the existing value
hashMap.get(2); // returns 1 
hashMap.remove(2); // remove the mapping for 2
hashMap.get(2);

java custom hashmap

custom hashmap