eBook – Guide Spring Cloud – NPI EA (cat=Spring Cloud)
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Let's get started with a Microservice Architecture with Spring Cloud:

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eBook – Mockito – NPI EA (tag = Mockito)
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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.

Get started with mocking and improve your application tests using our Mockito guide:

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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 – Reactive – NPI EA (cat=Reactive)
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Spring 5 added support for reactive programming with the Spring WebFlux module, which has been improved upon ever since. Get started with the Reactor project basics and reactive programming in Spring Boot:

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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 – Jackson – NPI EA (cat=Jackson)
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Do JSON right with Jackson

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eBook – HTTP Client – NPI EA (cat=Http Client-Side)
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Get the most out of the Apache HTTP Client

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eBook – Maven – NPI EA (cat = Maven)
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Get Started with Apache Maven:

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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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eBook – RwS – NPI EA (cat=Spring MVC)
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Building a REST API with Spring?

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Course – LS – NPI EA (cat=Jackson)
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Get started with Spring and Spring Boot, through the Learn Spring course:

>> LEARN SPRING
Course – RWSB – NPI EA (cat=REST)
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Explore Spring Boot 3 and Spring 6 in-depth through building a full REST API with the framework:

>> The New “REST With Spring Boot”

Course – LSS – NPI EA (cat=Spring Security)
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Yes, Spring Security can be complex, from the more advanced functionality within the Core to the deep OAuth support in the framework.

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.

You can explore the course here:

>> Learn Spring Security

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.

Get started with Spring Data JPA through the guided reference course:

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Partner – Moderne – NPI EA (cat=Spring Boot)
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Refactor Java code safely — and automatically — with OpenRewrite.

Refactoring big codebases by hand is slow, risky, and easy to put off. That’s where OpenRewrite comes in. The open-source framework for large-scale, automated code transformations helps teams modernize safely and consistently.

Each month, the creators and maintainers of OpenRewrite at Moderne run live, hands-on training sessions — one for newcomers and one for experienced users. You’ll see how recipes work, how to apply them across projects, and how to modernize code with confidence.

Join the next session, bring your questions, and learn how to automate the kind of work that usually eats your sprint time.

Course – LJB – NPI EA (cat = Core Java)
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Code your way through and build up a solid, practical foundation of Java:

>> Learn Java Basics

Partner – LambdaTest – NPI EA (cat= Testing)
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Distributed systems often come with complex challenges such as service-to-service communication, state management, asynchronous messaging, security, and more.

Dapr (Distributed Application Runtime) provides a set of APIs and building blocks to address these challenges, abstracting away infrastructure so we can focus on business logic.

In this tutorial, we'll focus on Dapr's pub/sub API for message brokering. Using its Spring Boot integration, we'll simplify the creation of a loosely coupled, portable, and easily testable pub/sub messaging system:

>> Flexible Pub/Sub Messaging With Spring Boot and Dapr

1. Overview

The JPA Criteria API can easily be used to add multiple AND/OR conditions when querying records in a database. In this tutorial, we’ll explore a quick example of JPA criteria queries that combine multiple AND/OR predicates.

If you’re not already familiar with predicates, we suggest reading about the basic JPA criteria queries first.

2. Sample Application

For our examples, we’ll consider an inventory of Item entities, each having an id, name, color, and grade:

@Entity
public class Item {

    @Id
    private Long id;
    private String color;
    private String grade;
    private String name;
    
    // standard getters and setters
}

3. Combining Two OR Predicates Using an AND Predicate

Let’s consider a scenario where we need to find items having both:

  1. red or blue color
    AND
  2. A or B grade

We can easily do this using JPA Criteria API’s and() and or() compound predicates.

To begin, we’ll set up our query:

CriteriaBuilder criteriaBuilder = entityManager.getCriteriaBuilder();
CriteriaQuery<Item> criteriaQuery = criteriaBuilder.createQuery(Item.class);
Root<Item> itemRoot = criteriaQuery.from(Item.class);

Now we’ll need to build a Predicate to find items having a blue or red color:

Predicate predicateForBlueColor
  = criteriaBuilder.equal(itemRoot.get("color"), "blue");
Predicate predicateForRedColor
  = criteriaBuilder.equal(itemRoot.get("color"), "red");
Predicate predicateForColor
  = criteriaBuilder.or(predicateForBlueColor, predicateForRedColor);

Next, we’ll build a Predicate to find items of grade A or B:

Predicate predicateForGradeA
  = criteriaBuilder.equal(itemRoot.get("grade"), "A");
Predicate predicateForGradeB
  = criteriaBuilder.equal(itemRoot.get("grade"), "B");
Predicate predicateForGrade
  = criteriaBuilder.or(predicateForGradeA, predicateForGradeB);

Finally, we’ll define the AND Predicate of these two, apply the where() method, and execute our query:

Predicate finalPredicate
  = criteriaBuilder.and(predicateForColor, predicateForGrade);
criteriaQuery.where(finalPredicate);
List<Item> items = entityManager.createQuery(criteriaQuery).getResultList();

4. Combining Two AND Predicates Using an OR Predicate

Conversely, let’s consider a scenario where we need to find items having either:

  1. red color and grade D
    OR
  2. blue color and grade B

The logic is quite similar, but here we create two AND Predicates first, and then combine them using an OR Predicate:

CriteriaBuilder criteriaBuilder = entityManager.getCriteriaBuilder();
CriteriaQuery<Item> criteriaQuery = criteriaBuilder.createQuery(Item.class);
Root<Item> itemRoot = criteriaQuery.from(Item.class);

Predicate predicateForBlueColor
  = criteriaBuilder.equal(itemRoot.get("color"), "red");
Predicate predicateForGradeA
  = criteriaBuilder.equal(itemRoot.get("grade"), "D");
Predicate predicateForBlueColorAndGradeA
  = criteriaBuilder.and(predicateForBlueColor, predicateForGradeA);

Predicate predicateForRedColor
  = criteriaBuilder.equal(itemRoot.get("color"), "blue");
Predicate predicateForGradeB
  = criteriaBuilder.equal(itemRoot.get("grade"), "B");
Predicate predicateForRedColorAndGradeB
  = criteriaBuilder.and(predicateForRedColor, predicateForGradeB);

Predicate finalPredicate
  = criteriaBuilder
  .or(predicateForBlueColorAndGradeA, predicateForRedColorAndGradeB);
criteriaQuery.where(finalPredicate);
List<Item> items = entityManager.createQuery(criteriaQuery).getResultList();

5. Conclusion

In this article, we used the JPA Criteria API to implement use cases where we needed to combine AND/OR predicates.

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.

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:

>> Download the eBook

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:

>> Download the eBook

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:

>> Join Pro and download the eBook

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

Explore the eBook

Course – LS – NPI EA (cat=REST)

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Get started with Spring Boot and with core Spring, through the Learn Spring course:

>> CHECK OUT THE COURSE

Partner – Moderne – NPI EA (tag=Refactoring)
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Modern Java teams move fast — but codebases don’t always keep up. Frameworks change, dependencies drift, and tech debt builds until it starts to drag on delivery. OpenRewrite was built to fix that: an open-source refactoring engine that automates repetitive code changes while keeping developer intent intact.

The monthly training series, led by the creators and maintainers of OpenRewrite at Moderne, walks through real-world migrations and modernization patterns. Whether you’re new to recipes or ready to write your own, you’ll learn practical ways to refactor safely and at scale.

If you’ve ever wished refactoring felt as natural — and as fast — as writing code, this is a good place to start.

Course – LSD – NPI (cat=JPA)
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Get started with Spring Data JPA through the reference Learn Spring Data JPA:

>> CHECK OUT THE COURSE

eBook Jackson – NPI EA – 3 (cat = Jackson)