Difference Between HashMap and HashTable (Interview)

The video tutorial explains the differences between hashmap and hashtable, focusing on synchronization, thread safety, handling of null values, and iteration methods. Hashmap is not synchronized and allows multiple threads to access it simultaneously, while hashtable is thread-safe, allowing only one thread at a time. Hashmap permits null keys and values, unlike hashtable. Iteration in hashmap uses the iterator interface, whereas hashtable requires the enumerator interface. These differences are crucial for understanding their use cases and are common interview questions.

What are the main differences between a HashMap and a HashTable?

Explain why a HashMap is considered non-synchronized.

What does it mean for a HashTable to be thread-safe?

Why does a HashMap allow null keys and values while a HashTable does not?

In what scenarios would you prefer to use a HashTable over a HashMap?

Describe how to iterate through objects in a HashMap compared to a HashTable.

What are the core differences that make HashMap and HashTable suitable for different use cases?