Phone interview starting with introducing yourself followed by core Java and design.

Pretty basic questions for a SSE position. I got an email of a video call, and was ready to do the interviews.

1. ArrayList vs HashMap
2. Multiple threads accessing a HashMap for get operation.
3. abstract class vs interface java when to use
4. Diamond problem
5. Parent and child class have same method but throws different errors
6. How are procedures executed in java
7. Authentication system design Db queries: a. inner join question, b. select dept names who have more than 2 employees ?