What does an ORM solution comprises of? | Java Hibernate

• It should have an API for performing basic CRUD (Create, Read, Update, Delete) operations on objects of persistent classes 
• Should have a language or an API for specifying queries that refer to the classes and the properties of classes 
• An ability for specifying mapping metadata 
• It should have a technique for ORM implementation to interact with transactional objects to perform dirty checking, lazy association fetching, and other optimization functions