From the course: Java Persistence API (JPA): 1 The Basics
Join today to access over 22,700 courses taught by industry experts or purchase this course individually.
Relationships - Java Tutorial
From the course: Java Persistence API (JPA): 1 The Basics
Relationships
- [Instructor] There are relationships between Java classes and there's relationships between entities. As a Java developer, representing relationships between classes is straightforward. But how do you translate those relationships to entities? More often than not, entities need to reference other entities. We will look at how we map relationships and dependencies, between entities using JPA. The object oriented world consists of classes and associations between classes. There are classes where one object links to another object. These relationships between classes have direction and cardinality. They can be bidirectional or unidirectional. In a bidirectional relationship each entity has a relationship field or property that refers to the other entity. In a unidirectional relationship only one entity has a relationship field or property that refers to the other. The cardinality captures the aspect of how many entities exist on each side of the relationship. So entities on the source…
Practice while you learn with exercise files
Download the files the instructor uses to teach the course. Follow along and learn by watching, listening and practicing.
Download courses and learn on the go
Watch courses on your mobile device without an internet connection. Download courses using your iOS or Android LinkedIn Learning app.