Hello Java and game developers and interested others,

at the moment I am learning Java. My colleagues and me are in a bootcamp and have a recap-time this week.
I want to create a game, that runs on a server and maybe later can be attached to Hive. This game is called Hamurabi.

The first part of it is to create a Spring Boot Server, which can handle some data.
So I started from scratch and here is the very first minimal viable product, a server which accepts http-requests:

Setting up Spring Boot, JPA and H2

I configure the server at start.spring.io:

I downloaded the zipfile and opened it in IntelliJ. I added the dependencies for Jackson into pom.xml:

        <dependency>
            <groupId>com.fasterxml.jackson.dataformat</groupId>
            <artifactId>jackson-dataformat-xml</artifactId>
        </dependency>

I have created the following two files data-sql and schema.sql:

I have adjusted application.properties:

So, after starting HammurabiApplication.java our Spring Database is up and running:

I can log into the SQL-Console via http://8099:h2-console

We find our data, which was automatically created (with the right settings in appliocation.properties) with the following command:

Setting up the data connection between Repository and Service

Now lets bring these repository data data to the service side on REST Spring:
We create the following packages: configuration, controller, dto, entity, repository and services:

In the folder "dto" we create the dataclass "Userlogdto" with the following content:

Please also create a default constructor to avoid the error message:
Ensure that org.chary.dto.Userlogdto has a non-private no-argument constructor.

Now we copy this file and paste it into the "entity" folder. We rename it to "UserlogEntity". We add "@Entity" and "@Table(name="Userlog") before the beginning of the class Userlog. And the @Id has to be set:

Don't forget to set the default Constructor to avoid the error message:
No default constructor for entity:

Now we create the interface "UserlogRepository" in the package "Repository"and we extend it with the class JPARepository<UserlogEntity, String>:

Now we build the Rest-Controller class and add the annotations
@RestController
@CrossOrigin("*")
@RequestMapping("/userlog")

Before we continue in the controller, we create the UserlogService interface. In this we create the method template
public List getAllUserlogs();

Now we add this Interface into the controller:

Now let's create the Interface-implementation in the service package and make it public to Spring by adding the annotation @Service:

Modelmapper

To get the objects, that are in the entity-class into the dto-class, we use modelmapper. Therefore we add it into the pom.xml

        <dependency>
            <groupId>org.modelmapper</groupId>
            <artifactId>modelmapper</artifactId>
            <version>2.3.5</version>
        </dependency>

Then we add the following to the UserlogServiceImpl-class:

We need to make modelmapper public to Spring. For this we create in the configuration package the ModelMapperConfiguration class.

I mixed up account and username. So I refactored it. But now it works:

If you want to see the complete code, click here. There are just some names exchanged.

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This is the very early beginning of my project. I hope I get the time and the knowledge to fulfil my dream to create, at least a small, game that uses HIVE to play it.

Regards, Achim