Is hashMap implemented as an array of linked lists

Question

While reading about HashMap I see that it is implemented as an array of buckets? Now are these buckets always linked lists? If so, why are they called buckets and not linked lists?

Answer 1

Looking at the source code of HashMap tells us that it's implemented as an array of Entries:

transient Entry[] table;

Each Entry has a field next, so they create a single linked list structure:

static class Entry<K,V> implements Map.Entry<K,V> {
    final K key;
    V value;
    Entry<K,V> next;

"Bucket" is a higher-level term, used in the literature and when explaining hash maps. Here "buckets" are implemented as a single linked lists.

Answer 2

In Java's Hashmap, the buckets are implemented as a linked list (each Entry has a reference to another entry called next).

The term "bucket" is referring to a concept. Linked list an implementation detail.