Introduction to Hibernate Training:
Hibernate training at Global online trainings – Hibernate is the implementation of JPA Specification which means it is one of the ORM framework implementers and it is one of the popular tools in the market. In fact it is the most popular tool in the market which implements JPA. The main job of Hibernate is to make sure that your Java Objects can map to database tables and you can write your objects in to rows or retrieve rows and map them to Java objects. It also provides data query, retrieval and creating criteria’s and few other things in its API’s. Global online trainings is best in providing Hibernate online training by industry experts at flexible timings.
Prerequisites of Hibernate Training:
- Knowledge on Java
- Basic knowledge on SQL Database.
Overview of Hibernate Training:
- In Java everything is an object that means if you want to make a software you have to think about objects. So it deals with the concept of OOPS which is inheritance, abstraction, polymorphism. So we talk about all these things when it comes to object.
- But when you want to store the data how do you do that? So normally when you say you want to show the data you might be storing that in a file which is your txt files, you might be storing data inside the XLS file. The problem is if you are storing data in this entire format it is very difficult to fetch, very difficult to process so for this we have concept of relational databases.
- One side we have Object model and the other side we have relational model. So we process data, we do all these software stuff with the help of objects and we store our data in a relational part. Are you interested to learn advance topics on this course? We provide best Hibernate training by real time experts with live projects.
That means if you are living in this world and if you want to connect software or your applications which works on objects with the relations you have to connect them? But is it that simple to connect?Let’s say you have RDBMS which is your MySQL and you have Java on the other side. So how do you connect your Java and MySQL? We have this concept of JDBC. So using this you can connect applications and you can connect your MySQL. The problem starts when you want to connect them in efficient way. Which means think as a developer and he has to write an application and all those data should be saved on the tables. So we want to achieve persistence, we want to store our data which is in the application into the database. Because in application we use variables, so we normally store our data inside variable and we have to make sure that data goes in to table.
Features of Hibernate training:
- In Objects we have classes, on the other side relational side we have tables, there we have the concept called fields, variables, on the other side we have columns, tuples. It is easy to map it, we have class, table, variables, fields. But can you implement all those oops concepts.
- So the industry people they wanted a mapping tool where you can Map your objects and relational properly and that’s why we have a concept called ORM which stands for Object Relational Mapping.
- When we say ORM it is just a concept but we wanted an implementation and that’s where we have some ORM tools. We have a tool which is Hibernate, Top link etc. So we have all these tools and one of the best tools to use is Hibernate.
- As per the ranking the best ORM tool is Hibernate. What Hibernate does is? It does the mapping between object world and relational world. Our consultants are highly skilled in Hibernate training from India.
ORM tool is used for persistent data. We are living in the world where you make different software’s and we can build all these software’s with the help of a language. One of the languages which we normally use to make applications is Java. When you make software, that software will be working with data of course now that data can be a normal variable or it can be objects. So when you are talking about normal variable, I am talking about primitive values or you might be having your data in the object format and when I say object format let’s say you have a class object and every object will have some data. Are you passionate in doing certifications? Global online trainings provide best Hibernate Certification training with 100% practical.
- Let’s say we have a class called student, we have three fields roll no, name, marks. Now if I create object of student it will be having three variables so that will be one object. So if I create object of student it will be having three values. I want to make sure that those values are getting stored somewhere and that somewhere is your database. Now this database can be anything it can be MySQL training, Oracle, it can be SQL server; we have different DBMS to work with.
- We use database so that we can store data and that concept of storing data is called as persistence. By default when you talk about variables those are transient which means we normally don’t store data in the inside database directly.
- So what we do is we create variables, objects and those are temporary data. If you want to store that data we need to use databases. Normally to connect to your Java application with database we use a concept of JDBC which stands for Java Database Connectivity. The moment you say that you are walking with JDBC and we have a database. So for sure we need to use something called as SQL language and not everyone is comfortable with SQL.
- In fact people who only learn Java, they might not be comfortable with SQL and the moment you say you want to work with database now you need to know SQL. So we wanted a solution where you can store the data into database but without using SQL.
- I mean as a programmer I don’t want to use SQL query that is the first concern. The second one is If I have an object which is Obj and this Obj object is of Student which will have three values, I want to store these values in to database. So to work with SQL what we normally do is we write an SQL query.
- What if in Java if you have this Object Obj here if you can directly store the data inside database simply by saying hey framework save my object that’s it the moment you say save Obj you work is done. That data is getting stored inside database your job is done but how is it possible? Can we store an object into database directly because normally when you say database we are actually taking about RDBMS type of databases which is relational databases where you have rows and columns.
We are trying to create a relationship between the object oriented programming concepts and the relational database system and that is possible with the help of ORM which is object that is your Java concept, Relational that is your database concepts and we have to map it. The problem is ORM is just a concept. How can you implement ORM? We need to use some tools which are ORM tools and one of the tools of ORM is your Hibernate. Again Hibernate is not the only tool we have iBattis, JPA and top link which is from Oracle.
What you can do with Hibernate?
You can store your objects into database directly with the help of save method but how do we use the save method? It is very simple, to use save method we need to create an object of session. For that we need to create an object of session factory because using this we can create sessions and in session factory you have to provide configuration details of database. Again there are multiple ways of configuarations , we can use XML way, Java configuration way. Not just saving we can also use get method to fetch the values or to fetch the data. We have save and get methods so we can use all these concepts to implement Hibernate and trust me this is the awesome tool available in ORM. ORM is not just a technology which came accidentally, it was well planned. If you are making application when you want to persist this data.
What is JPA?
- JPA stands for Java Persistence API. JPA training is a specification which was defined as part of Ejb 3.0 and now it is the industry standard for ORM. JPA provides API for managing relational data in Java based applications that means you can persist Java objects as database rows or you can retrieve rows and map them to Java Objects or manage the objects which talk to the databases using ORM like JPA.
- The mapping between Java objects and database table rows are done, the combination of XML and Java annotations. So for example there are two Java objects which talk to the database so you might want to convert the instance of Java Object into a table row or you might want to retrieve a row from a database table and map it to a Java Object. So these things can be done if ORM is configured so that objects can talk to the ORM and ORM in turn talks to the database.
So your objects can directly map to the database table without the use of SQL. So here JPA plays the role of ORM. Some of the common classes in JPA API are EntityManagerFactory, EntityManager. Apart from that there are many more annotations for example there are annotations for restricting values and there are annotations for managing the transaction etc. There are several versions of JPA but the current version is JPA 2.1. Finally, you need to remember that JPA is just a specification, it needs implementation for the application to connect to the database.
Conclusion of Hibernate training:
Want to know the best part? In the background Hibernate generates SQL statements which are compatible with the database to which it is connecting that means if you are connecting to Oracle you are connecting to MySQL if there are any syntactical differences in the queries in certain situations or those two databases, Hibernate will take care of translating it to suit the database. It also means that your application can switch the database while the upper layer will be unaware of the changes in the database. So you don’t need to change any upper layer. So if your application today uses MySQL and tomorrow you want to switch to Postgresql or Oracle or SQLServer your code should not change.Only thing which is going to change is the configuration in the Hibernate configuration file or the Mapping file. There are lots of opportunities in the market for Hibernate training with the exciting packages. Join in Global online trainings for best Hibernate online training by real time experts from India. Hurry Up!!