# Quarkus Annotation cheatSheet!!

![Quarkus - Hello world example using Kotlin!](https://cdn.hashnode.com/res/hashnode/image/upload/v1655907435341/9WO-oSR5A.png?w=1600&h=840&fit=crop&crop=entropy&auto=compress,format&format=webp align="left")

In this article, you are going to learn some of the most commonly used annotations in Quarkus and their purposes:

### **Quarkus Core Annotations**

* `@ApplicationScoped`: Used to annotate a class whose instances are shared across the entire application. It is a type of CDI scope that defines the lifecycle of the annotated bean to be the same as the lifecycle of the application.
    
* `@Singleton`: Used to annotate a class whose instances are shared across the entire application. It is a type of CDI scope that defines the lifecycle of the annotated bean to be the same as the lifecycle of the application.
    
* `@Inject`: Used to annotate a field, constructor parameter, or setter method to indicate that the value of the field or parameter should be injected by CDI.
    
* `@Produces`: Used to annotate a method that produces a bean to be injected by CDI.
    
* `@ConfigProperty`: Used to annotate a field, constructor parameter, or setter method to indicate that its value should be injected from the configuration.
    

### RESTful Web Services Annotations

* `@Path`: Used to annotate a resource class or method to specify the URI path that should be mapped to the resource.
    
* `@GET`: Used to annotate a method to indicate that it should handle HTTP GET requests.
    
* `@POST`: Used to annotate a method to indicate that it should handle HTTP POST requests.
    
* `@PUT`: Used to annotate a method to indicate that it should handle HTTP PUT requests.
    
* `@DELETE`: Used to annotate a method to indicate that it should handle HTTP DELETE requests.
    
* `@Produces`: Used to annotate a method to indicate the media type of the response it produces.
    

### **Hibernate Annotations**

* `@Entity`: Used to annotate a class to indicate that it is a persistent entity in the database.
    
* `@Id`: Used to annotate a field to indicate that it is the primary key of the entity.
    
* `@GeneratedValue`: Used to annotate a field to specify the strategy used to generate the primary key value.
    
* `@Column`: Used to annotate a field to specify the mapping between the entity attribute and the database column.
    

### Quarkus Messaging Annotations

* `@Incoming`: Used to annotate a method to indicate that it should handle incoming messages from a messaging system.
    
* `@Outgoing`: Used to annotate a method to indicate that it produces outgoing messages to a messaging system.
    
* `@Channel`: Used to annotate a method to indicate the name of the messaging channel.
    

These are just a few of the most commonly used annotations in Quarkus. There are many more annotations available that provide additional functionality, such as caching, security, and metrics.

I hope this helps, you!!

**More such articles:**

[https://medium.com/techwasti](Link)

[https://www.youtube.com/channel/UCiTaHm1AYqMS4F4L9zyO7qA](Link)

[https://www.techwasti.com/](Link)

\==========================\*\*=========================

**If this article adds any value to you then please clap and comment.**

**Let’s connect on** [**Stackoverflow**](http://stackoverflow.com/users/3187349/maheshwar-ligade)**,** [**LinkedIn**](https://in.linkedin.com/in/maheshwar-ligade-14447841)**, &** [**Twitter**](https://twitter.com/MaheshwarLigade)**.**