stackoverflow hibernate interview questions

#Stackoverflow hibernate interview questions pro#
#Stackoverflow hibernate interview questions code#

In this case, you can choose to insert a Hibernate specific annotation directly in your class since JPA does not provide the interface to do that thing. There are cases where Hibernate may give you features that are not codified in JPA.

#Stackoverflow hibernate interview questions code#

You can code toward JPA and pick whatever compliant ORM vendor suits your needs. Hibernate now becomes one of the many vendors that implement the JPA 2.0 specification. This is only the API and not the implementation. The API is provided in the JDK as a set of interfaces so that your classes can depend on the javax.persistence and not worry about the particular vendor that is doing the work of persisting your objects. These are specifications of a generic Java Persistence API. Meanwhile, the JCP with a lot of input from Hibernate and other ORM tool vendors was developing JSR 220 (Java Specification Request) which resulted in JPA 1.0 (2006) and eventually JSR 317 which is JPA 2.0 (2009). Hence the need for a generic persistence API. The fundamental issue now is that your code becomes tightly coupled with a specific vendor(Hibernate) for what a lot of people thought should be more generic. Hibernate provided an implementation to do this and the API to drive the implementation either through XML config or annotations. You notify hibernate about your Entity objects and it automatically generates the strategy to persist them. Hibernate (in 2003) provided a way to abstract SQL and allow developers to think more in terms of persisting objects (ORM). For various reasons that function may become part of the Java JDK through the JCP (Java Community Process) Often there are third parties that develop packages that perform a function or fill a gap that are not part of the official JDK. Some things are too hard to understand without a historical perspective of the language and understanding of the JCP. Is there a book that takes a problem/solution approach to JPA2? 'Pro JPA2' seems more like a bible and reference on JPA2 (It doesn't get into Queries until the later half of the book).

Can you recommend a good practical JPA2 book.

Is JPA2 supposed to be used with a 'JPA Provider' e.g TopLink or Hibernate? If so, then what's the benefit of using JPA2 + Hibernate as compared to JPA2 alone, or compared to Hibernate alone ?.

Using JPA2 alone can I fetch data from DB by simply annotating my POJO's.This confuses me so I have a few questions: If you think a feature should be standardized, you should speak up

#Stackoverflow hibernate interview questions pro#

I picked up Pro JPA2 book and it keeps referring to 'JPA provider'. I have experience using iBatis and now I'm trying to learn either Hibernate or JPA2. But from a practical point of view, what really is the difference? Also, I understand that Hibernate has more features than JPA 2. I understand that JPA 2 is a specification and Hibernate is a tool for ORM. It is not currently accepting new answers or interactions. This question and its answers are locked because the question is off-topic but has historical significance.