gs-rest-service

Built using...

• A Mac
• Atom
• Java JDK 1.8
• Gradle 2.10

The steps...

1. Create a project folder

mkdir gs-rest-service
cd gs-rest-service

2. Create a Gradle build script

touch build.gradle
atom build.gradle

Copy the contents from this Initial Gradle build script to the build.gradle file

3. Create the project directory structure

mkdir -p src/main/java/hello

4. Create a resource representation class

touch src/main/java/hello/Greeting.java
atom src/main/java/hello/Greeting.java

Add the following

package hello;

public class Greeting {

    private final long id;
    private final String content;

    public Greeting(long id, String content) {
        this.id = id;
        this.content = content;
    }

    public long getId() {
        return id;
    }

    public String getContent() {
        return content;
    }
}

5. Create a resource controller

touch src/main/java/hello/GreetingController.java
atom src/main/java/hello/GreetingController.java

Add the following

package hello;

import java.util.concurrent.atomic.AtomicLong;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class GreetingController {

    private static final String template = "Hello, %s!";
    private final AtomicLong counter = new AtomicLong();

    @RequestMapping("/greeting")
    public Greeting greeting(@RequestParam(value="name", defaultValue="World") String name) {
        return new Greeting(counter.incrementAndGet(),
                            String.format(template, name));
    }
}

6. Make it executable

touch src/main/java/hello/Application.java
atom src/main/java/hello/Application.java

Add the following

package hello;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class Application {

    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }
}

7. Run it

• The one liner

gradle bootRun

• Build and run

gradle Build
java -jar build/libs/gs-rest-service-0.1.0.jar

8. Test the thing

http://localhost:8080/greeting

{"id":1,"content":"Hello, World!"}

http://localhost:8080/greeting?name=bob

{"id":2,"content":"Hello, bob!"}