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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.

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

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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:

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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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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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1. Introduction

YAML is a human-friendly notation used in configuration files. Why would we prefer this data serialization over the properties file in Spring Boot? Besides readability and reduction of repetition, YAML is the perfect language to write Configuration as Code for the deployments.

In the same way, the use of YAML for Spring DevOps facilitates the storage of the configuration variables in the environment as the 12 Factor Authenticator recommends.

In this tutorial, we’ll compare Spring YAML versus properties file in order to check the main advantages of using one over the other. But remember, the selection of YAML over properties file configuration is sometimes a decision of personal taste.

2. YAML Notation

YAML stands for a recursive acronym for “YAML Ain’t Markup Language“. It provides the following characteristics:

  • More clarity and human-friendliness
  • Perfect for hierarchical configuration data
  • It supports enhance capabilities such as maps, lists, and scalar types

Those capabilities make YAML the perfect companion for Spring configuration files.  A word of caution here for those starting out with YAML: writing it can be a bit tedious at the beginning due to its indentation rules.

Let’s see how it works!

3. Spring YAML Configuration

As it was mentioned in the previous sections, YAML is an extraordinary data format for configuration files. It’s much more readable, and it provides enhanced capabilities over the properties file. Therefore, it makes sense to recommend this notation over the properties file configuration. Furthermore, from version 1.2, YAML is a superset of JSON.

In addition, in Spring the configuration files placed outside the artifact override those inside the packaged jar. Another interesting feature of Spring configuration is the possibility to assign environment variables at runtime. This is extremely important for DevOps deployments.

Spring profiles allow separating the environments and apply different properties to them. YAML adds the possibility to include several profiles in the same file.

Note: this feature is also supported for properties files with Spring Boot 2.4.0.

In our case, for deployment purposes, we’ll have three: testing, development, and production:

spring:
  profiles:
    active:
    - test

---

spring:
  config:
    activate:
      on-profile: test
name: test-YAML
environment: testing
servers:
  - www.abc.test.com
  - www.xyz.test.com
  
---

spring:
  config:
    activate:
      on-profile: prod
name: prod-YAML
environment: production
servers:
  - www.abc.com
  - www.xyz.com
    
---

spring:
  config:
    activate:
      on-profile: dev
name: ${DEV_NAME:dev-YAML}
environment: development
servers:
  - www.abc.dev.com
  - www.xyz.dev.com

Note: if we use a Spring Boot version prior to 2.4.0, we should use the spring.profiles property instead of the spring.config.activate.on-profile we used here.

Let’s now check the spring.profiles.active property which assigns the test environment by default. We can redeploy the artifact using different profiles without building again the source code.

Another interesting feature in Spring is that you can enable the profile via the environment variable:

export SPRING_PROFILES_ACTIVE=dev

We’ll see the relevance of this environment variable in the Testing section. Finally, we can configure YAML properties assigning directly the value from the environment:

name: ${DEV_NAME:dev-YAML}

We can see that if no environment variable is configured, a default value dev-YAML is used.

4. Reduction of Repetition and Readability

The hierarchical structure of YAML provides ways of reducing the upper levels of the configuration properties file. Let’s see the differences with an example:

component:
  idm:
    url: myurl
    user: user
    password: password
    description: >
      this should be a long 
      description
  service:
    url: myurlservice
    token: token
    description: >
      this should be another long 
      description

The same configuration would become redundant using properties file:

component.idm.url=myurl
component.idm.user=user
component.idm.password=password
component.idm.description=this should be a long \
                          description
component.service.url=myurlservice
component.service.token=token
component.service.description=this should be another long \ 
                              description

The hierarchical nature of YAML greatly enhances legibility. It is not only a question of avoiding repetitions but also the indentation, well used, perfectly describes what the configuration is about and what is for. With YAML, as in the case of properties file with a backslash \, it is possible to break the content into multiple lines with > character.

5. Lists and Maps

We can configure lists and maps using YAML and properties file.

There are two ways to assign values and store them in a list:

servers:
  - www.abc.test.com
  - www.xyz.test.com
  
external: [www.abc.test.com, www.xyz.test.com]

Both examples provide the same result. The equivalent configuration using properties file would be more difficult to read:

servers[0]=www.abc.test.com
servers[1]=www.xyz.test.com

external=www.abc.test.com, www.xyz.test.com

Again YAML version is more human-readable and clear.

In the same way, we can configure maps:

map:
  firstkey: key1
  secondkey: key2

6. Testing

Now, let’s check if everything is working as expected. If we check the logging of the application, we can see that the environment selected by default is testing:

2020-06-11 13:58:28.846  INFO 10720 --- [main] com.baeldung.yaml.MyApplication: ...
using environment:testing
name:test-YAML
servers:[www.abc.test.com, www.xyz.test.com]
external:[www.abc.test.com, www.xyz.test.com]
map:{firstkey=key1, secondkey=key2}
Idm:
   Url: myurl
   User: user
   Password: password
   Description: this should be a long description

Service:
   Url: myurlservice
   Token: token
   Description: this should be another long description

We can overwrite the name by configuring DEV_NAME in the environment:

export DEV_NAME=new-dev-YAML

We can see that the name of the environment changes executing the application with dev profile:

2020-06-11 17:00:45.459  INFO 19636 --- [main] com.baeldung.yaml.MyApplication: ...
using environment:development
name:new-dev-YAML
servers:[www.abc.dev.com, www.xyz.dev.com]

Let’s run for the production environment using SPRING_PROFILES_ACTIVE=prod:

export SPRING_PROFILES_ACTIVE=prod

2020-06-11 17:03:33.074  INFO 20716 --- [main] ...
using environment:production
name:prod-YAML
servers:[www.abc.com, www.xyz.com]

7. Conclusion

In this tutorial, we described the intricacies of the use of YAML configuration compared to the properties file.

We showed that YAML provides human friendliness capabilities, it reduces repetition and is more concise than its properties file variant.

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:

>> 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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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)
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