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Baeldung Pro comes with both absolutely No-Ads as well as finally with Dark Mode, for a clean learning experience:

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

Partner – Microsoft – NPI EA (cat = Baeldung)
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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 – 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.

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

eBook – Guide Spring Cloud – NPI EA (cat=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.

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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.

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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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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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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:

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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:

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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 – All Access – NPI EA (cat= Spring)
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All Access is finally out, with all of my Spring courses. Learn JUnit is out as well, and Learn Maven is coming fast. And, of course, quite a bit more affordable. Finally.

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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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Partner – LambdaTest – NPI EA (cat=Testing)
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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.

When coupled with LambdaTest (an AI-powered cloud-based test execution platform) it can be further scaled to run the Playwright scripts in parallel across 3000+ browser and device combinations:

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Course – Spring Sale 2025 – NPI EA (cat= Baeldung)
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Course – Spring Sale 2025 – NPI (cat=Baeldung)
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Yes, we're now running our Spring Sale. All Courses are 25% off until 26th May, 2025:

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1. Introduction

Spring Boot CLI is a command-line abstraction that allows us to easily run Spring micro-services expressed as Groovy scripts. It also provides simplified and enhanced dependency management for those services.

This short article takes a quick look at how to configure Spring Boot CLI and execute simple terminal commands to run pre-configured micro-services.

We’ll use Spring Boot CLI 2.0.0.RELEASE for this article. The newest version of Spring Boot CLI can be found over at Maven Central.

2. Setting Up Spring Boot CLI

One of the easiest ways to set up Spring Boot CLI is to use SDKMAN. Setup and installation instructions for SDKMAN can be found here.

After installing SDKMAN, run the following command to automatically install and configure Spring Boot CLI:

$ sdk install springboot

To verify the install, run the command:

$ spring --version

We can also install Spring Boot CLI by compiling from source, and Mac users can use pre-built packages from Homebrew or MacPorts. See the official docs for all installation options.

3. Common Terminal Commands

Spring Boot CLI provides several useful commands and features out-of-the-box. One of the most helpful features is Spring Shell, which wraps commands with the necessary spring prefix.

To start the embedded shell, we run:

spring shell

From here, we can directly enter desired commands without pre-pending the spring keyword (since we’re now in spring shell).

For example, we can display the current version of the running CLI by typing:

version

One of the most important commands is telling Spring Boot CLI to run a Groovy script:

run [SCRIPT_NAME].groovy

Spring Boot CLI will either automatically infer the dependencies or will do so given the correctly supplied annotations. After this, it will launch an embedded web container and app.

Let’s take a closer look at how to use Groovy script with Spring Boot CLI!

4. Essential Groovy Scripts

Groovy and Spring come together with Spring Boot CLI to allow powerful, performant micro-services to be quickly scripted in single-file Groovy deployments.

Support for multiply-scripted applications usually requires additional build tools like Maven or Gradle.

Below we’ll cover some of the most common use-cases for Spring Boot CLI, reserving more complex setups for other articles.

For a list of all Spring-supported Groovy annotations, please check out the official docs.

4.1. @Grab

The @Grab annotation and Groovy’s Java-esque import clauses allow for easy dependency management and injection.

In fact, most annotations abstract, simplify, and automatically include the necessary import statements. This allows us to spend more time thinking about architecture and the underlying logic of the services we want to deploy.

Let’s take a look at how to use the @Grab annotation:

package org.test

@Grab("spring-boot-starter-actuator")

@RestController
class ExampleRestController{
  //...
}

As we can see, spring-boot-starter-actuator comes pre-configured allowing for succinct script deployment without requiring a customized application or environmental properties, XML, or other programmatic configuration, though each of those things can be specified when necessary.

The full list of @Grab arguments — each specifying a library to download and import — is available here.

4.2. @Controller, @RestController, and @EnableWebMvc

To further expedite deployment, we can alternatively utilize Spring Boot CLI’s provided “grab hints” to automatically infer correct dependencies to import.

We’ll go over some of the most common use cases below.

For example, we can use the familiar @Controller and @Service annotations to quickly scaffold a standard MVC controller and service:

@RestController
class Example {
 
    @Autowired
    private MyService myService;

    @GetMapping("/")
    public String helloWorld() {
        return myService.sayWorld();
    }
}

@Service
class MyService {
    public String sayWorld() {
        return "World!";
    }
}

Spring Boot CLI supports all default configuration for Spring Boot. So, we can our Groovy apps will automatically access static resources from their usual default locations.

4.3. @EnableWebSecurity

To add Spring Boot Security options to our app, we can use the @EnableWebSecurity annotation, which will then be automatically downloaded by Spring Boot CLI.

Below, we’ll abstract part of this process using the spring-boot-starter-security dependency, which leverages the @EnableWebSecurity annotation under the hood:

package bael.security

@Grab("spring-boot-starter-security")

@RestController
class SampleController {

    @RequestMapping("/")
    public def example() {
        [message: "Hello World!"]
    }
}

For more details on how to protect resources and handle security, please check out the official documentation.

4.4. @Test

To set up a simple JUnit test, we can add the @Grab(‘junit’) or @Test annotations:

package bael.test

@Grab('junit')
class Test {
    //...
}

This will allow us to execute JUnit tests easily.

4.5. DataSource and JdbcTemplate

Persistent data options can be specified including DataSource or JdbcTemplate without explicitly using the @Grab annotation:

package bael.data

@Grab('h2')
@Configuration
@EnableWebMvc
@ComponentScan('bael.data')
class DataConfig {

    @Bean
    DataSource dataSource() {
        return new EmbeddedDatabaseBuilder()
          .setType(EmbeddedDatabaseType.H2).build();
    }

}

By simply using familiar Spring bean configuration conventions, we’ve grabbed the H2 embedded database and set it as the DataSource.

5. Custom Configuration

There are two primary ways to configure a Spring Boot micro-service using Spring Boot CLI:

  1. we can add argument parameters to our terminal commands
  2. we can use a customized YAML file to provide an application configuration

Spring Boot will automatically search the /config directory for application.yml or application.properties

├── app
    ├── app.groovy
    ├── config
        ├── application.yml
    ...

We can also set up:

├── app
    ├── example.groovy
    ├── example.yml
    ...

A full list of application properties can be found here at Spring.

6. Conclusion

This concludes our quick walk-through of Spring Boot CLI! For more details, check out the official docs.

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)
announcement - icon

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)
announcement - icon

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:

>> 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?

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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

Course – Spring Sale 2025 – NPI EA (cat= Baeldung)
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Yes, we're now running our Spring Sale. All Courses are 25% off until 26th May, 2025:

>> EXPLORE ACCESS NOW

Course – Spring Sale 2025 – NPI (All)
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Yes, we're now running our Spring Sale. All Courses are 25% off until 26th May, 2025:

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Partner – Microsoft – NPI (cat=Spring)
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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.

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