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Azure Container Apps is a fully managed serverless container service that enables you to build and deploy modern, cloud-native Java applications and microservices at scale. It offers a simplified developer experience while providing the flexibility and portability of containers.

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Partner – Microsoft – NPI EA (cat= Spring Boot)
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Azure Container Apps is a fully managed serverless container service that enables you to build and deploy modern, cloud-native Java applications and microservices at scale. It offers a simplified developer experience while providing the flexibility and portability of containers.

Of course, Azure Container Apps has really solid support for our ecosystem, from a number of build options, managed Java components, native metrics, dynamic logger, and quite a bit more.

To learn more about Java features on Azure Container Apps, you can get started over on the documentation page.

And, you can also ask questions and leave feedback on the Azure Container Apps GitHub page.

Partner – Orkes – NPI EA (cat=Spring)
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Modern software architecture is often broken. Slow delivery leads to missed opportunities, innovation is stalled due to architectural complexities, and engineering resources are exceedingly expensive.

Orkes is the leading workflow orchestration platform built to enable teams to transform the way they develop, connect, and deploy applications, microservices, AI agents, and more.

With Orkes Conductor managed through Orkes Cloud, developers can focus on building mission critical applications without worrying about infrastructure maintenance to meet goals and, simply put, taking new products live faster and reducing total cost of ownership.

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Partner – Orkes – NPI EA (tag=Microservices)
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Modern software architecture is often broken. Slow delivery leads to missed opportunities, innovation is stalled due to architectural complexities, and engineering resources are exceedingly expensive.

Orkes is the leading workflow orchestration platform built to enable teams to transform the way they develop, connect, and deploy applications, microservices, AI agents, and more.

With Orkes Conductor managed through Orkes Cloud, developers can focus on building mission critical applications without worrying about infrastructure maintenance to meet goals and, simply put, taking new products live faster and reducing total cost of ownership.

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Mocking is an essential part of unit testing, and the Mockito library makes it easy to write clean and intuitive unit tests for your Java code.

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Since its introduction in Java 8, the Stream API has become a staple of Java development. The basic operations like iterating, filtering, mapping sequences of elements are deceptively simple to use.

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To get a better understanding on how Streams work and how to combine them with other language features, check out our guide to Java Streams:

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Explore Spring Boot 3 and Spring 6 in-depth through building a full REST API with the framework:

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I built the security material as two full courses - Core and OAuth, to get practical with these more complex scenarios. We explore when and how to use each feature and code through it on the backing project.

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Course – LSD – NPI EA (tag=Spring Data JPA)
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Spring Data JPA is a great way to handle the complexity of JPA with the powerful simplicity of Spring Boot.

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End-to-end testing is a very useful method to make sure that your application works as intended. This highlights issues in the overall functionality of the software, that the unit and integration test stages may miss.

Playwright is an easy-to-use, but powerful tool that automates end-to-end testing, and supports all modern browsers and platforms.

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1. Overview

In this quick article, we’ll focus on different kinds of Spring Data repository interfaces and their functionality. We’ll touch on:

  • CrudRepository
  • PagingAndSortingRepository
  • JpaRepository

Simply put, every repository in Spring Data extends the generic Repository interface, but beyond that, they each have different functionality.

2. Spring Data Repositories

Let’s start with the JpaRepository – which extends PagingAndSortingRepository and, in turn, the CrudRepository.

Each of these defines its functionality:

And so, because of this inheritance relationship, the JpaRepository contains the full API of CrudRepository and PagingAndSortingRepository.

When we don’t need the full functionality provided by JpaRepository and PagingAndSortingRepository, we can use the CrudRepository.

Let’s now look at a quick example to understand these APIs better.

We’ll start with a simple Product entity:

@Entity
public class Product {

    @Id
    private long id;
    private String name;

    // getters and setters
}

And let’s implement a simple operation – find a Product based on its name:

@Repository
public interface ProductRepository extends JpaRepository<Product, Long> {
    Product findByName(String productName);
}

That’s all. The Spring Data Repository will auto-generate the implementation based on the name we provided it.

This was a very simple example, of course; you can go deeper into Spring Data JPA here.

3. CrudRepository

Let’s now have a look at the code for the CrudRepository interface:

public interface CrudRepository<T, ID extends Serializable>
  extends Repository<T, ID> {

    <S extends T> S save(S entity);

    T findOne(ID primaryKey);

    Iterable<T> findAll();

    Long count();

    void delete(T entity);

    boolean exists(ID primaryKey);
}

Notice the typical CRUD functionality:

  • save(…) – save an Iterable of entities. Here, we can pass multiple objects to save them in a batch
  • findOne(…) – get a single entity based on passed primary key value
  • findAll() – get an Iterable of all available entities in the database
  • count() – return the count of total entities in a table
  • delete(…) – delete an entity based on the passed object
  • exists(…) – verify if an entity exists based on the passed primary key value

This interface looks quite generic and simple, but actually, it provides all the basic query abstractions needed in an application.

4. PagingAndSortingRepository

Now, let’s have a look at another repository interface, which extends CrudRepository:

public interface PagingAndSortingRepository<T, ID extends Serializable> 
  extends CrudRepository<T, ID> {

    Iterable<T> findAll(Sort sort);

    Page<T> findAll(Pageable pageable);
}

This interface provides a method findAll(Pageable pageable), which is the key to implementing Pagination.

When using Pageable, we create a Pageable object with certain properties, and we’ve to specify at least the following:

  1. Page size
  2. Current page number
  3. Sorting

So, let’s assume that we want to show the first page of a result set sorted by lastName, ascending, having no more than five records each. This is how we can achieve this using a PageRequest and a Sort definition:

Sort sort = new Sort(new Sort.Order(Direction.ASC, "lastName"));
Pageable pageable = new PageRequest(0, 5, sort);

Passing the pageable object to the Spring data query will return the results in question (the first parameter of PageRequest is zero-based).

5. JpaRepository

Finally, we’ll have a look at the JpaRepository interface:

public interface JpaRepository<T, ID extends Serializable> extends
  PagingAndSortingRepository<T, ID> {

    List<T> findAll();

    List<T> findAll(Sort sort);

    List<T> save(Iterable<? extends T> entities);

    void flush();

    T saveAndFlush(T entity);

    void deleteInBatch(Iterable<T> entities);
}

Again, let’s look at each of these methods in brief:

  • findAll() – get a List of all available entities in the database
  • findAll(…) – get a List of all available entities and sort them using the provided condition
  • save(…) – save an Iterable of entities. Here, we can pass multiple objects to save them in a batch
  • flush() – flush all pending tasks to the database
  • saveAndFlush(…) – save the entity and flush changes immediately
  • deleteInBatch(…) – delete an Iterable of entities. Here, we can pass multiple objects to delete them in a batch

Clearly, the above interface extends PagingAndSortingRepository, which means it also has all methods present in the CrudRepository.

6. Spring Data Repositories in Spring Data 3

In the new version of Spring Data, the internals of some Repository classes have changed slightly, adding new functionalities and providing a simpler development experience.

We now have access to the advantageous List-based CRUD repository interface. Also, the class hierarchy of some spring-data Repository classes is based on a different structure.

All details are available in our New CRUD Repository Interfaces in Spring Data 3 article.

7. Downsides of Spring Data Repositories

Beyond all the very useful advantages of these repositories, there are some basic downsides of directly depending on these as well:

  1. We couple our code to the library and to its specific abstractions, such as `Page` or `Pageable`; that’s, of course, not unique to this library – but we do have to be careful not to expose these internal implementation details
  2. By extending, e.g. CrudRepository, we expose a complete set of persistence methods at once. This is probably fine in most circumstances as well, but we might run into situations where we’d like to gain more fine-grained control over the methods exposed, e.g. to create a ReadOnlyRepository that doesn’t include the save(…) and delete(…) methods of CrudRepository

8. Conclusion

This article covered some brief but important differences and features of Spring Data JPA repository interfaces. For more information, have a look at the series on Spring Persistence.

The code backing this article is available on GitHub. Once you're logged in as a Baeldung Pro Member, start learning and coding on the project.
Baeldung Pro – NPI EA (cat = Baeldung)
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Baeldung Pro comes with both absolutely No-Ads as well as finally with Dark Mode, for a clean learning experience:

>> Explore a clean Baeldung

Once the early-adopter seats are all used, the price will go up and stay at $33/year.

Partner – Microsoft – NPI EA (cat = Spring Boot)
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Azure Container Apps is a fully managed serverless container service that enables you to build and deploy modern, cloud-native Java applications and microservices at scale. It offers a simplified developer experience while providing the flexibility and portability of containers.

Of course, Azure Container Apps has really solid support for our ecosystem, from a number of build options, managed Java components, native metrics, dynamic logger, and quite a bit more.

To learn more about Java features on Azure Container Apps, visit the documentation page.

You can also ask questions and leave feedback on the Azure Container Apps GitHub page.

Partner – Orkes – NPI EA (cat = Spring)
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Modern software architecture is often broken. Slow delivery leads to missed opportunities, innovation is stalled due to architectural complexities, and engineering resources are exceedingly expensive.

Orkes is the leading workflow orchestration platform built to enable teams to transform the way they develop, connect, and deploy applications, microservices, AI agents, and more.

With Orkes Conductor managed through Orkes Cloud, developers can focus on building mission critical applications without worrying about infrastructure maintenance to meet goals and, simply put, taking new products live faster and reducing total cost of ownership.

Try a 14-Day Free Trial of Orkes Conductor today.

Partner – Orkes – NPI EA (tag = Microservices)
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Modern software architecture is often broken. Slow delivery leads to missed opportunities, innovation is stalled due to architectural complexities, and engineering resources are exceedingly expensive.

Orkes is the leading workflow orchestration platform built to enable teams to transform the way they develop, connect, and deploy applications, microservices, AI agents, and more.

With Orkes Conductor managed through Orkes Cloud, developers can focus on building mission critical applications without worrying about infrastructure maintenance to meet goals and, simply put, taking new products live faster and reducing total cost of ownership.

Try a 14-Day Free Trial of Orkes Conductor today.

eBook – HTTP Client – NPI EA (cat=HTTP Client-Side)
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The Apache HTTP Client is a very robust library, suitable for both simple and advanced use cases when testing HTTP endpoints. Check out our guide covering basic request and response handling, as well as security, cookies, timeouts, and more:

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eBook – Java Concurrency – NPI EA (cat=Java Concurrency)
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Handling concurrency in an application can be a tricky process with many potential pitfalls. A solid grasp of the fundamentals will go a long way to help minimize these issues.

Get started with understanding multi-threaded applications with our Java Concurrency guide:

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eBook – Java Streams – NPI EA (cat=Java Streams)
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Since its introduction in Java 8, the Stream API has become a staple of Java development. The basic operations like iterating, filtering, mapping sequences of elements are deceptively simple to use.

But these can also be overused and fall into some common pitfalls.

To get a better understanding on how Streams work and how to combine them with other language features, check out our guide to Java Streams:

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eBook – Persistence – NPI EA (cat=Persistence)
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Working on getting your persistence layer right with Spring?

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Course – LS – NPI EA (cat=REST)

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Course – Spring Sale 2025 – NPI EA (cat= Baeldung)
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Course – Spring Sale 2025 – NPI (All)
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eBook Jackson – NPI EA – 3 (cat = Jackson)