Developers use variables in Java to hold data, with all variables having a data type and a name. The data type determines the values that a variable can hold. In this tutorial, you’ll learn how ...

Object-oriented systems are usually partitioned into layers of related responsibilities and only dependencies in one direction are allowed, from higher layers (more specific, less reusable) to lower ...

Persistence is one of the greatest challenges for building applications. There are many options for building persistence layers. Data Access Objects (DAO) is a popular design pattern for building the ...

The Jakarta Persistence API (JPA) is a Java specification that bridges the gap between relational databases and object-oriented programming. This two-part tutorial introduces JPA and explains how ...