In this example I am going to show you how we can implement One to Many(@OneToMany) relationship using JPA persistence API in Java.
The Java Persistence API (JPA) is a Java specification for accessing, persisting, and managing data between Java objects / classes and a relational database.
The JPA is used to reduce the burden of writing codes for relational object management, a programmer or developer follows the ‘JPA Provider’ framework, which allows easy interaction with database instance. The JPA being a Java framework a programmer also needs not to worry about the SQL part of the code, he/she may need to hardly concentrate on SQL coding.
In this One to Many mapping example, we have Teacher and Period relationship. A class period can be taken by multiple teachers at different times.