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Hibernate - Why need Hibernate

The most common approach to Java persistence is for application programmers to work directly with SQL and JDBC. After all, developers are familiar with relational database management systems, they understand SQL, and they how how to work with tables and foreign keys. Moreover, they can always use the well-known and widely used data access object patttern to hide complex JDBC code and nonportable SQL from the business logic.  However, this work usually ends up consuming a large portion of the development effort. Furthermore, when requirements change, a hand-codes solution always requires more attention and maintenance effort.

A ORM implementation is a complex beast - less complex than an application server, but more complex than a web application framework like Struts. Why should we introduce another complex infrastructural element into our system?Will it be worth it?
A supposed advantage of ORM (object/relational mapping) is that it shields developers from messy SQL.

Now, let's look at some of the benefits of ORM and Hibernate:
Productivity: Persistence-related code can be perhaps the most tedious code in a Java application. Hibernate eliminates much of the grunt work and lets you concentrate on the business problem -No matter which application-development strategy you prefer - top-down, starting with a domain model, or bottom-up, starting with an existing database schema.

Maintainability: Fewer lines of code(LOC) make the system more understandable, because it emphasizes business logic rather than plumbing. In systems with hand-coded persistence, an inevitable tension exists between the relational representation and the object model implementing the domain. Changes to one always involve changes to the others. ORM provides a buffer between the two models, allowing more elegant use of object orientation on the Java side, and insulating each model from minor changes to the other.

Performance: The people who implemented your ORM software had much more time to investigate the performance optimizations than you have.

Vendor independence: An ORM abstracts your application away from the underlying SQL database and SQL dialect.

I really don't want to use SQL again and again even for very simple relationship project. Hibernate will help to mediate the application's interaction with a relational database, leaving the developer free to concentrate on the business problem at hand.


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