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Partner – Frontegg – expanded (cat = Security)
announcement - icon User management is very complex, when implemented properly. No surprise here.

Not having to roll all of that out manually, but instead integrating a mature, fully-fledged solution - yeah, that makes a lot of sense.
That's basically what Frontegg is - User Management for your application. It's focused on making your app scalable, secure and enjoyable for your users.
From signup to authentication, it supports simple scenarios all the way to complex and custom application logic.

Have a look:

>> Elegant User Management, Tailor-made for B2B SaaS

Partner – Frontegg – expanded (cat = Spring Security)
announcement - icon User management is very complex, when implemented properly. No surprise here.

Not having to roll all of that out manually, but instead integrating a mature, fully-fledged solution - yeah, that makes a lot of sense.
That's basically what Frontegg is - User Management for your application. It's focused on making your app scalable, secure and enjoyable for your users.
From signup to authentication, it supports simple scenarios all the way to complex and custom application logic.

Have a look:

>> Elegant User Management, Tailor-made for B2B SaaS

NPI – Spring Top – Temp – Non-Geo (Lightrun)

Get started with Spring 5 and Spring Boot 2, through the reference Learn Spring course:

>> LEARN SPRING
NPI – Lightrun – Spring (partner)

We rely on other people’s code in our own work. Every day. It might be the language you’re writing in, the framework you’re building on, or some esoteric piece of software that does one thing so well you never found the need to implement it yourself.

The problem is, of course, when things fall apart in production - debugging the implementation of a 3rd party library you have no intimate knowledge of is, to say the least, tricky. It’s difficult to understand what talks to what and, specifically, which part of the underlying library is at fault.

Lightrun is a new kind of debugger.

It's one geared specifically towards real-life production environments. Using Lightrun, you can drill down into running applications, including 3rd party dependencies, with real-time logs, snapshots, and metrics. No hotfixes, redeployments, or restarts required.

Learn more in this quick, 5-minute Lightrun tutorial:

>> The Essential List of Spring Boot Annotations and Their Use Cases

1. Introduction

In this quick tutorial, we're going to learn about the differences between the @Component, @Repository, and @Service annotations in the Spring Framework.

Further reading:

Guide to Spring @Autowired

A guide to the most commonest usage of Springs @Autowired annotation and qualifiers

The Spring @Qualifier Annotation

@Autowired alone isn't sometimes enough to disambiguate dependencies. You can wire more exactly using the @Qualifier annotation. @Primary can also help.

2. Spring Annotations

In most typical applications, we have distinct layers like data access, presentation, service, business, etc.

Additionally, in each layer we have various beans. To detect these beans automatically, Spring uses classpath scanning annotations.

Then it registers each bean in the ApplicationContext.

Here's a quick overview of a few of these annotations:

  • @Component is a generic stereotype for any Spring-managed component.
  • @Service annotates classes at the service layer.
  • @Repository annotates classes at the persistence layer, which will act as a database repository.

We already have an extended article about these annotations, so we'll keep the focus here to the differences between them.

3. What's Different?

The major difference between these stereotypes is that they are used for different classifications. When we annotate a class for auto-detection, we should use the respective stereotype.

Now let's go through them in more detail.

3.1. @Component

We can use @Component across the application to mark the beans as Spring's managed components. Spring will only pick up and register beans with @Component, and doesn't look for @Service and @Repository in general.

They are registered in ApplicationContext because they are annotated with @Component:

@Component
public @interface Service {
}
@Component
public @interface Repository {
}

@Service and @Repository are special cases of @Component. They are technically the same, but we use them for the different purposes.

3.2. @Repository

@Repository’s job is to catch persistence-specific exceptions and re-throw them as one of Spring’s unified unchecked exceptions.

For this, Spring provides PersistenceExceptionTranslationPostProcessor, which we are required to add in our application context (already included if we're using Spring Boot):

<bean class=
  "org.springframework.dao.annotation.PersistenceExceptionTranslationPostProcessor"/>

This bean post processor adds an advisor to any bean that’s annotated with @Repository.

3.3. @Service

We mark beans with @Service to indicate that they're holding the business logic. Besides being used in the service layer, there isn't any other special use for this annotation.

4. Conclusion

In this article, we learned about the differences between the @Component, @Repository, and @Service annotations. We examined each annotation separately to understand their areas of use.

In conclusion, it's always a good idea to choose the annotation based on their layer conventions.

Spring bottom

Get started with Spring 5 and Spring Boot 2, through the Learn Spring course:

>> THE COURSE
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