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?

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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:

>> 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

When we want to enable or disable the embedded Tomcat server in a Spring Boot application, we need to consider different approaches based on our application’s requirements. By default, Spring Boot provides an embedded Tomcat server, but in some cases, we might want to disable it.

For applications that require an embedded server, we can use the default configuration. However, for applications that do not expose web endpoints or need to run as background services, disabling Tomcat can optimize resource usage.

In this tutorial, we’ll explore when to enable or disable the embedded Tomcat server and how to configure Spring Boot profiles to achieve this dynamically.

2. Understanding Embedded Tomcat in Spring Boot

Spring Boot simplifies application deployment by bundling an embedded Tomcat server within the application’s executable JAR file. This approach eliminates the need to install and configure an external Tomcat instance, making development and deployment more efficient for us.

Spring Boot uses Spring Boot Starters to include the necessary dependencies for embedded Tomcat. The default starter, spring-boot-starter-web, automatically configures and initializes Tomcat when present in the classpath.

2.1. Advantages of Embedded Tomcat

Spring Boot’s embedded Tomcat server offers several benefits:

  • Simplified deployment: No need to install an external Tomcat server
  • Self-contained applications: The application can be packaged as a JAR file and run anywhere
  • Automatic configuration: Spring Boot configures Tomcat automatically based on dependencies
  • Flexibility: Can be easily replaced with other embedded servers like Jetty or Undertow

2.2. When to Disable Tomcat Server

While embedded Tomcat is useful, there are cases where disabling it is beneficial to us:

  • Non-web applications: Applications that don’t serve HTTP requests, such as CLI tools or batch jobs
  • Microservices with alternative servers: Some services may use a dedicated web server like Nginx
  • Resource optimization: Disabling Tomcat reduces memory and CPU usage

3. Configuring Spring Boot Profiles

Spring Boot provides us with the spring.profiles.active property to define environment-specific configurations. We can create different profile-based configurations to control whether our embedded Tomcat server is enabled or not.

To define profiles, we typically create separate configuration files such as:

  • application-dev.properties (for development with Tomcat enabled)
  • application-batch.properties (for batch processing without Tomcat)

4. Disabling Embedded Tomcat with Profiles

Spring Boot determines whether to enable an embedded web server based on the spring.main.web-application-type property. We can set it to NONE to disable the embedded Tomcat.

To do this in a profile-specific configuration, we modify the application-batch.properties file:

spring.main.web-application-type=NONE

When this profile is active, Spring Boot will not start Tomcat, treating the application as a non-web service.

Alternatively, we can configure this setting using YAML:

spring:
  main:
    web-application-type: NONE

5. Example Configuration for Different Profiles

Let’s configure an application with two profiles:

  • Development Profile (dev) – Tomcat enabled (default setting).
  • Batch Profile (batch) – Tomcat disabled.

To ensure that our embedded Tomcat server starts normally, let’s set the property in our application-dev.properties file:

spring.main.web-application-type=SERVLET

To disable our embedded Tomcat server for batch processing, let’s set the property in our application-batch.properties file:

spring.main.web-application-type=NONE

6. Switching Between Profiles

Once we’ve defined multiple profile configurations, we can activate the desired profile via the application.properties file:

spring.profiles.active=batch

Alternatively, we can pass it as a command-line argument:

java -Dspring.profiles.active=batch -jar myapp.jar

This flexibility allows us to switch between web-enabled and non-web modes as needed during development, testing, or production deployment.

7. Conclusion

Spring Boot allows flexible configuration of the embedded Tomcat server using profiles. By leveraging spring.main.web-application-type, we can disable Tomcat when needed for non-web applications, optimizing resource usage and deployment configurations. Using profile-based settings or dynamic Java logic ensures that our application adapts to different environments seamlessly.

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)