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

>> Join Pro and download the eBook

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:

>> Download the eBook

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:

>> Join Pro and 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 – 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

Download the E-book

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

Download the E-book

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?

Download the E-book

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:

>> CHECK OUT THE COURSE

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.

Partner – LambdaTest – NPI EA (cat=Testing)
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Regression testing is an important step in the release process, to ensure that new code doesn't break the existing functionality. As the codebase evolves, we want to run these tests frequently to help catch any issues early on.

The best way to ensure these tests run frequently on an automated basis is, of course, to include them in the CI/CD pipeline. This way, the regression tests will execute automatically whenever we commit code to the repository.

In this tutorial, we'll see how to create regression tests using Selenium, and then include them in our pipeline using GitHub Actions:, to be run on the LambdaTest cloud grid:

>> How to Run Selenium Regression Tests With GitHub Actions

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

1. Overview

IntelliJ is a trendy integrated development environment (IDE) tool for code development. It is an intelligent code assistance that enhances code productivity and fastens development work. Additionally, it follows a structured way to organize the project directory. Also, it is used in various programming languages like Python, Java, Kotlin, Lua, and many more.

In this tutorial, we’ll learn how to enable the line number in IntelliJ in different ways. Furthermore, allowing the line to number in the project is a handy feature in writing and debugging code.

2. Enable Line Number Globally

Enabling the line number is a straightforward task as it enhances code productivity and the experience for developers. Furthermore, it helps in writing code quickly and effectively. In IntelliJ, we can enable this feature globally and file-specific.

To demonstrate, let’s first look at enabling this feature globally for all projects:

  • Open the IntelliJ IDEA IDE
  • Click on the IntelliJ IDEA in the top menu
  • Click on Settings
  • Click on Editor > General > Appearance
  • Check the box next to Show line numbers

The above-explained entire process is visible in the GUI below:

Global

This way, we can easily enable the line number for all the projects added to IDEA. Furthermore, restarting the IDE can also ensure that the changes have been remembered.

3. Enable Line Number per File

In IntelliJ IDEA, we can also enable a line number per file basis. Using this method, we can further control which files display line numbers in the code. To illustrate, let’s look at the steps to enable line numbers for a specific file:

  • Open the IntelliJ IDEA IDE
  • Pick a file from a project
  • Right-click on the left marker of the opened file
  • Select Appearance from the list
  • Check the box next to show line numbers

To illustrate, let’s look at the GUI of the above process:

File Basis

Enabling a line number per file basis allows developers to customize the code settings. As a result, we can further optimize resource usage and improve code readability, navigation, and collaboration by customizing the specific needs of the code file.

4. Using the Shortcut Key

By enabling a line, we can jump directly to the specific line of code within the code, which makes navigation easier. Additionally, it assists in identifying code errors, reviewing code documentation, and finding duplicate code. Furthermore, we can enable this line in IntelliJ by using shortcuts. To illustrate, let’s look at the process step-by-step:

  • Open the IntelliJ IDEA IDE
  • Press the Shift key twice
  • Type/Search line number
  • Enter to enable/disable the feature

In the below, we can see the final GUI to enable/disable the line number:

Shortcut

The above approach is beneficial and handy to enable/disable this feature. Furthermore, with a keyboard shortcut, we can easily toggle the absence of a line number in our code.

5. Conclusion

In this article, we explored various ways to enable line numbers in IntelliJ IDEA. First, we looked at enabling line numbers for all the projects inside the IDE. After that, we also looked at performing the same for a specific file.

Finally, we enabled the line number using a keyboard shortcut.

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.

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