HIBERNATE FRAMEWORK OVERVIEW AND FEATURES

Posted by ShaleshRana on October 5th, 2018

Hibernate ORM or simply Hibernate is referred to as a tool for object-relational mapping for Java programming language. Hibernate delivers a framework for mapping an object-oriented domain model to a relational database. This takes care of object-relational impedance mismatch problems. All of this is done by replacing direct, persistent database accesses with high-level object handling functions. Hibernate is dispersed under the GNU Lesser General Public License 2.1 and is free to use.

The most common Hibernate Interview Question is regarding the functions and the advantages of Hibernate. Listed below are few of the advantages of using hibernate:

• Hibernate performs the mapping of Java classes to database tables utilizing XML files while keeping every line of the code same.

• For the purpose of storing and retrieving Java objects directly to and from the database by providing simple APIs

• If the user wants to affect some changes in the database or any table, he does not need to go through a detailed process; he only needs to alter the XML file properties.

• Forms an abstract of the unknown SQL types and also provides a way of working around the simple Java Objects.

• An application server is not important for hibernate to operate.

• Minimizes the database access with strategies which are smart fetching.

• Hibernate is based on a layered architecture which enables the user to operate without knowing all the underlying APIs. Hibernate uses database and configuration data for providing persistence services and persistent objects to the applications.

• It is capable of removing the much repetitive code from the JDBC API, and therefore, the code is much easier to be read, written, and supported.

• Hibernate Query Language (HQL) is a fully object-oriented and more close to the Java programming language comparing to SQL in JDBC. Also, HQL is a Database-independent query which permits the users to switch between different databases easily.

• Hibernate supports caching, which enhances performance.

• First-level is a mandatory Session cache.

• Second-level is an optional cache. Hibernate has many cache providers for this level; the well-known ones are JBoss, EHCache, OSCache, warm cache etc.

• Query-level is an optional cache for the query result sets.

• Lazy load which also enhances the performance.

• Hibernate supports the JPA annotations, which means that the code is portable to the other ORM frameworks.

• Hibernate is known to have a connection pool.

• The user is to required to handle exceptions. Hibernate permits the database management (for example creating tables), JDBC can only work with the existing DB tables.

• Hibernate supports the inheritance, associations, and collections which are not available in the JDBC API.

In essence, Hibernate is a well-built object model which is quite useful both in programming and debugging. Building an object is not that easy. While programming language like Java is object-oriented, and this represents data as an interconnected graph of objects, relational database, quite contrary, data is represented in a tabular format (like a spreadsheet).A user has to handle the mismatch between an object model and a relational model if a user decides to write such a tier, the overall time and work required in programming and debug the model, is always proportional to the scale of your system. All of these make data persistence very difficult.