'Program to an interface, not an implementation.' What does it mean ? Why should you pass Interfaces around instead of Classes ? abstract class What is Multi-path Inheritance inheritance ? How do you implement it in Java ? What are the disadvantages of OOPS ? What is JIT compiler & how does it work ? Benefits of Pooling & Singleton ? What are deadlocks in Java & how do you prevent them ? Should you store image & video data in database ? If yes, then which column type should you use ? Explain how this query will be processed by MySQL: SELECT Table_Name, Category FROM Product GROUP BY Name, Category HAVING COUNT(id) > 1; What are the different ways in which you can optimize DB Queries, and when do you use them ? DSA Questions Rotate Matrix by 90 degree Search in Rotated Array Sort Colors Contiguous Array