Hibernate Relationships - Hibernate Relationships mapping example

In this tutorial we will learn how to create relationships among the Entity. We will learn Hibernation Relationships mapping in detail with the example code. You can download the code and then try on your computer. The Eclipse IDE can be used to run the Hibernate Relationships examples. You can easily import the project into Eclipse IDE. 

The relational databases support one-to-one, one-to-many, many-to-many and many-to-one relationships. We can simulate the all these relationships in our Java. With the help of Hibernate relationships we can define these associations among the persistence unit and use in the Java program.

With the help of annotations and the xml meta-data once can create the Entity relationships. Hibernate will then use the relationships metadata to persist the data into database tables. For example you can create the object of master entity and add the child entity into the master entity and then save the master entity. This will save master and child entity into the database.

The Java 5 annotation and xml meta-data can be use to define the relationships among the persistence classes. Let's learn the Hibernate annotations in details.

Hibernate annotations using xml files

The following tutorial will provide you the examples of creating relationships using the xml meta-data. Let's learn it one by one:

1. Setting up database
   In this section we will create the MySQL database and required tables to run the examples.
    
2. Hibernate one-to-one using hbm.xml file
   This section we will see the the structure of Entity classes and the one-to-one mapping tags in the .hbm.xml file. We will also run the example and see the data into database.
    
3. Hibernate one-to-many relationships example using hbm.xml file
   Here you will learn one-to-many relationships developed using the hmb.xml file. The one-to-one tag is used to define the relationships.
    
4. Hibernate many-to-many relationships example using hbm.xml file
   Now we will learn many-to-many relationships. Let's try many-to-many example.
    
5. Hibernate many-to-one relationships example using hbm.xml file
   Let's develop the many to one relationship.