{"id":33848,"date":"2014-12-03T07:00:48","date_gmt":"2014-12-03T05:00:48","guid":{"rendered":"http:\/\/www.javacodegeeks.com\/?p=33848"},"modified":"2014-12-02T12:20:06","modified_gmt":"2014-12-02T10:20:06","slug":"spring-data-jpa-tutorial-introduction","status":"publish","type":"post","link":"https:\/\/www.javacodegeeks.com\/2014\/12\/spring-data-jpa-tutorial-introduction.html","title":{"rendered":"Spring Data JPA Tutorial: Introduction"},"content":{"rendered":"

Creating repositories that use the Java Persistence API is a cumbersome process that takes a lot of time and requires a lot of boilerplate code. We can eliminate some boilerplate code by following these steps:
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  1. Create an abstract base repository class that provides CRUD operations for entities.<\/li>\n
  2. Create the concrete repository class that extends the abstract base repository class.<\/li>\n<\/ol>\n

    The problem of this approach is that we still have to write the code that creates our database queries and invokes them. To make matters worse, we have to do this every time when we want to create a new database query. This is a waste of time<\/strong>.<\/p>\n

    What would you say if I would tell you that we can create JPA repositories without writing any boilerplate code?<\/p>\n

    The odds are that you might not believe me, but Spring Data JPA helps us to do just that. The website of the Spring Data JPA project states that<\/a>:<\/p>\n

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    Implementing a data access layer of an application has been cumbersome for quite a while. Too much boilerplate code has to be written to execute simple queries as well as perform pagination, and auditing. Spring Data JPA aims to significantly improve the implementation of data access layers by reducing the effort to the amount that\u2019s actually needed. As a developer you write your repository interfaces, including custom finder methods, and Spring will provide the implementation automatically\n<\/p>\n<\/blockquote>\n

    This blog post provides an introduction to Spring Data JPA. We will learn what Spring Data JPA really is and take a quick look at the Spring Data repository interfaces.<\/p>\n

    Let\u2019s get started.<\/p>\n

    What Spring Data JPA Is?<\/h2>\n

    Spring Data JPA is not a JPA provider<\/strong>. It is a library \/ framework that adds an extra layer of abstraction on the top of our JPA provider. If we decide to use Spring Data JPA, the repository layer of our application contains three layers that are described in the following:<\/p>\n