Helidon

Helidon is a Java framework for writing microservices. IntelliJ IDEA provides the following:

Coding assistance specific to both Helidon SE and Helidon MP
Integration with the Bean Validation, CDI, and Endpoints tool windows
A dedicated project creation wizard based on start.microprofile.io

Create a new Helidon project

From the main menu, select File | New | Project.
In the New Project wizard, select MicroProfile and choose the Default starter service https://start.microprofile.io.
Click Next.
Configure the following MicroProfile project settings:
- Group: com.example
- Artifact: hello-helidon
- MicroProfile version: MP32
- MicroProfile Runtime: Helidon
Click Next.
Select the necessary specifications for your application and click Next.
If necessary, change the project name, location, and other settings. Click Finish.

The generated project contains a REST endpoint named HelloController with the following code:

        package com.example.hello.helidon;

        import javax.inject.Singleton;
        import javax.ws.rs.GET;
        import javax.ws.rs.Path;

        /**
         *
         */
        @Path("/hello")
        @Singleton
        public class HelloController {

            @GET
            public String sayHello() {
                return "Hello World";
            }
        }
    

You can open the Endpoints tool window (View | Tool Windows | Endpoints) and see this endpoint:

HelloController endpoint in the Endpoints tool window

Run the Helidon application

Open the io.helidon.microprofile.server.Main class from the Helidon library.
In the gutter, click and run the Main.main() method Ctrl+Shift+F10.
In the Edit Configuration dialog, set Use classpath of module to your application's module: hello-helidon.
Click Run.

In the Run tool window, you will see that the server is running on http://localhost:8080. Open this URL in a web browser to see the landing page of the MicroProfile server.

The default root is located at /data, as defined by @ApplicationPath("/data") in the HellohelidonRestApplication class. Open http://localhost:8080/data/hello to see the output produced by the HelloController endpoint: Hello World.

Last modified: 02 August 2022