How do you use Hashmap, Hashset, ArrayList , [ ]

[lilzz]

what's the difference between Hashmap and Hashset?

The difference betwen ArrayList versus Arrayname [ ]

[razor]

maps (hashpam) keep keys and corresponding values, sets keep only keys.
ArrayList is an implementation of List interface, handy class for managing list of objects.
array_name[] - is just an array (however it's a class too) - basic thing (something like basic type)

why don't you ask google? do you know what is google?

[ghp]

Hello,

see also the java tutorial, especially https://docs.oracle.com/javase/tutorial ... index.html

Regards,
Gerhard