Data

Tools

Indexes

Applications

Experiments

Awesome

An open API service indexing awesome lists of open source software.

https://github.com/spring-petclinic/spring-petclinic-jooq

Spring PetClinic Sample Application built with jOOQ (Java Object Oriented Querying)
https://github.com/spring-petclinic/spring-petclinic-jooq

jooq jooq-codegen

Last synced: 5 months ago
JSON representation

Spring PetClinic Sample Application built with jOOQ (Java Object Oriented Querying)

Awesome Lists containing this project

README 

          
# Spring PetClinic Sample Application built with jOOQ [![Build Status](https://github.com/spring-petclinic/spring-petclinic-jooq/actions/workflows/maven-build.yml/badge.svg)](https://github.com/spring-petclinic/spring-petclinic-jooq/actions/workflows/maven-build.yml)[![Build Status](https://github.com/spring-petclinic/spring-petclinic-jooq/actions/workflows/gradle-build.yml/badge.svg)](https://github.com/spring-petclinic/spring-petclinic-jooq/actions/workflows/gradle-build.yml)



[![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/#https://github.com/spring-petclinic/spring-petclinic-jooq) [![Open in GitHub Codespaces](https://github.com/codespaces/badge.svg)](https://github.com/codespaces/new?hide_repo_select=true&ref=main&repo=7517918)



This is a fork of the official [Spring PetClinic](https://github.com/spring-projects/spring-petclinic) application with domain & persistence layer 

built with [jOOQ](https://www.jooq.org/) instead of [Spring Data JPA](https://projects.spring.io/spring-data-jpa/).



## What is jOOQ?



**jOOQ** (**Java Object Oriented Querying**) is a database-mapping library that generates Java code from your database schema and 

allows you to build **type-safe SQL queries** through its **fluent API**. Unlike JPA, which follows an object-first approach, 

jOOQ takes a SQL-first approach, giving developers precise control over the SQL being executed while maintaining type safety.



## jOOQ vs Spring Data JPA



| Feature                    | jOOQ                                         | Spring Data JPA                              |

|----------------------------|----------------------------------------------|----------------------------------------------|

| Approach                   | SQL-first                                    | Object-first                                 |

| Code generation            | Generates Java code from database schema     | Generates database schema from Java entities |

| Query building             | Fluent API for SQL queries                   | Method names and annotations                 |

| SQL control                | Precise control over SQL statements          | SQL generation handled by ORM                |

| Performance                | Better for complex queries                   | Optimized for basic CRUD operations          |

| Type safety                | Compile-time checking of SQL queries         | Limited compile-time checking                |

| Learning curve             | Steeper for ORM developers                   | More familiar for Java developers            |

| Caching & state management | No built-in caching or entity state tracking | Built-in caching and entity state management |

| Verbosity                  | Very verbose. Queries can be factored.       | Very concise for simple CRUD operation       |

| License                    | Commercial license for some features         | Open Source (Apache 2.0)                     |



This Spring Petclinic implementation demonstrates how jOOQ can be used within a Spring Boot application to 

provide type-safe SQL queries with precise control over database operations.



## What are the differences with the original Spring Petclinic?



The main differences with the original Spring Petclinic application are:

- The domain and persistence layer is built using **jOOQ instead of Spring Data JPA**.

- The `pom.xml` and `build.gradle` files are updated to include jOOQ dependencies and plugins.

The `jooqCodegen` plugin is used to **generate the Java code from the H2 database schema**. You may switch to MySQL or PostgreSQL. 

See the [Database configuration](#database-configuration) section for more details.

- With JPA, [Java records can’t be entities](https://thorben-janssen.com/java-records-hibernate-jpa/#records-cant-be-entities).

With jOOQ, we could use some **Java records** as domain entities. The `Vet`, `Vets`, `Specialty`, `PetType` and `Visit` classes has been converted to records.

  Due to a limitation of the Spring MVC binding, the classes `Owner` and `Pet` remain as they are.



## Understanding the Spring Petclinic application with a few diagrams



[See the presentation here](https://speakerdeck.com/michaelisvy/spring-petclinic-sample-application)



## Run Petclinic locally



Spring Petclinic is a [Spring Boot](https://spring.io/guides/gs/spring-boot) application built using [Maven](https://spring.io/guides/gs/maven/) or [Gradle](https://spring.io/guides/gs/gradle/). You can build a jar file and run it from the command line (it should work just as well with Java 17 or newer):



```bash

git clone https://github.com/spring-petclinic/spring-petclinic-jooq.git

cd spring-petclinic

./mvnw package

java -jar target/*.jar

```



(On Windows, or if your shell doesn't expand the glob, you might need to specify the JAR file name explicitly on the command line at the end there.)



You can then access the Petclinic at .



petclinic-screenshot



Or you can run it from Maven directly using the Spring Boot Maven plugin. If you do this, it will pick up changes that you make in the project immediately (changes to Java source files require a compile as well - most people use an IDE for this):



```bash

./mvnw spring-boot:run

```



> NOTE: If you prefer to use Gradle, you can build the app using `./gradlew build` and look for the jar file in `build/libs`.



## Building a Container



There is no `Dockerfile` in this project. You can build a container image (if you have a docker daemon) using the Spring Boot build plugin:



```bash

./mvnw spring-boot:build-image

```



## In case you find a bug/suggested improvement for Spring Petclinic



Our issue tracker is available [here](https://github.com/spring-petclinic/spring-petclinic-jooq/issues).



## Database configuration



In its default configuration, Petclinic uses an in-memory database (H2) which

gets populated at startup with data. The h2 console is exposed at `http://localhost:8080/h2-console`,

and it is possible to inspect the content of the database using the `jdbc:h2:mem:` URL. The UUID is printed at startup to the console.



A similar setup is provided for MySQL and PostgreSQL if a persistent database configuration is needed. Note that whenever the database type changes, the app needs to run with a different profile: `spring.profiles.active=mysql` for MySQL or `spring.profiles.active=postgres` for PostgreSQL. See the [Spring Boot documentation](https://docs.spring.io/spring-boot/how-to/properties-and-configuration.html#howto.properties-and-configuration.set-active-spring-profiles) for more detail on how to set the active profile.



For PostgreSQL, you have to change the `defaultNameCase` property in the `jooqCodegen` plugin configuration to `lower` in the `pom.xml` or `build.gradle` file, as PostgreSQL treats unquoted identifiers as lower case by default. This is not necessary for MySQL.

Regenerate the jOOQ code after changing the database type by running the jOOQ codegen plugin again:

```bash

./mvnw compile org.jooq:jooq-codegen-maven:generate

```



You can start MySQL or PostgreSQL locally with whatever installer works for your OS or use docker:



```bash

docker run -e MYSQL_USER=petclinic -e MYSQL_PASSWORD=petclinic -e MYSQL_ROOT_PASSWORD=root -e MYSQL_DATABASE=petclinic -p 3306:3306 mysql:9.1

```



or



```bash

docker run -e POSTGRES_USER=petclinic -e POSTGRES_PASSWORD=petclinic -e POSTGRES_DB=petclinic -p 5432:5432 postgres:17.0

```



Further documentation is provided for [MySQL](https://github.com/spring-petclinic/spring-petclinic-jooq/blob/main/src/main/resources/db/mysql/petclinic_db_setup_mysql.txt)

and [PostgreSQL](https://github.com/spring-petclinic/spring-petclinic-jooq/blob/main/src/main/resources/db/postgres/petclinic_db_setup_postgres.txt).



Instead of vanilla `docker` you can also use the provided `docker-compose.yml` file to start the database containers. Each one has a service named after the Spring profile:



```bash

docker compose up mysql

```



or



```bash

docker compose up postgres

```



## Test Applications



At development time we recommend you use the test applications set up as `main()` methods in `PetClinicIntegrationTests` (using the default H2 database and also adding Spring Boot Devtools), `MySqlTestApplication` and `PostgresIntegrationTests`. These are set up so that you can run the apps in your IDE to get fast feedback and also run the same classes as integration tests against the respective database. The MySql integration tests use Testcontainers to start the database in a Docker container, and the Postgres tests use Docker Compose to do the same thing.



## Compiling the CSS



There is a `petclinic.css` in `src/main/resources/static/resources/css`. It was generated from the `petclinic.scss` source, combined with the [Bootstrap](https://getbootstrap.com/) library. If you make changes to the `scss`, or upgrade Bootstrap, you will need to re-compile the CSS resources using the Maven profile "css", i.e. `./mvnw package -P css`. There is no build profile for Gradle to compile the CSS.



## Working with Petclinic in your IDE



### Prerequisites



The following items should be installed in your system:



- Java 17 or newer (full JDK, not a JRE)

- [Git command line tool](https://help.github.com/articles/set-up-git)

- Your preferred IDE

  - Eclipse with the m2e plugin. Note: when m2e is available, there is an m2 icon in `Help -> About` dialog. If m2e is

  not there, follow the install process [here](https://www.eclipse.org/m2e/)

  - [Spring Tools Suite](https://spring.io/tools) (STS)

  - [IntelliJ IDEA](https://www.jetbrains.com/idea/)

  - [VS Code](https://code.visualstudio.com)



### Steps



1. On the command line run:



    ```bash

    git clone https://github.com/spring-petclinic/spring-petclinic-jooq.git

    ```



1. Inside Eclipse or STS:



    Open the project via `File -> Import -> Maven -> Existing Maven project`, then select the root directory of the cloned repo.



    Then either build on the command line `./mvnw generate-resources` or use the Eclipse launcher (right-click on project and `Run As -> Maven install`) to generate the CSS. Run the application's main method by right-clicking on it and choosing `Run As -> Java Application`.



1. Inside IntelliJ IDEA:



    In the main menu, choose `File -> Open` and select the Petclinic [pom.xml](pom.xml). Click on the `Open` button.



    - CSS files are generated from the Maven build. You can build them on the command line `./mvnw generate-resources` or right-click on the `spring-petclinic` project then `Maven -> Generates sources and Update Folders`.



    - A run configuration named `PetClinicApplication` should have been created for you if you're using a recent Ultimate version. Otherwise, run the application by right-clicking on the `PetClinicApplication` main class and choosing `Run 'PetClinicApplication'`.



1. Navigate to the Petclinic



    Visit [http://localhost:8080](http://localhost:8080) in your browser.



## Looking for something in particular?



|Spring Boot Configuration | Class or Java property files  |

|--------------------------|---|

|The Main Class | [PetClinicApplication](https://github.com/spring-petclinic/spring-petclinic-jooq/blob/main/src/main/java/org/springframework/samples/petclinic/PetClinicApplication.java) |

|Properties Files | [application.properties](https://github.com/spring-petclinic/spring-petclinic-jooq/blob/main/src/main/resources) |

|Caching | [CacheConfiguration](https://github.com/spring-petclinic/spring-petclinic-jooq/blob/main/src/main/java/org/springframework/samples/petclinic/system/CacheConfiguration.java) |



## Interesting Spring Petclinic branches and forks



The Spring Petclinic "main" branch in the [spring-projects](https://github.com/spring-petclinic/spring-petclinic-jooq)

GitHub org is the "canonical" implementation based on Spring Boot and Thymeleaf. There are

[quite a few forks](https://spring-petclinic.github.io/docs/forks.html) in the GitHub org

[spring-petclinic](https://github.com/spring-petclinic). If you are interested in using a different technology stack to implement the Pet Clinic, please join the community there.



## Interaction with other open-source projects



One of the best parts about working on the Spring Petclinic application is that we have the opportunity to work in direct contact with many Open Source projects. We found bugs/suggested improvements on various topics such as Spring, Spring Data, Bean Validation and even Eclipse! In many cases, they've been fixed/implemented in just a few days.

Here is a list of them:



| Name | Issue |

|------|-------|

| Spring JDBC: simplify usage of NamedParameterJdbcTemplate | [SPR-10256](https://github.com/spring-projects/spring-framework/issues/14889) and [SPR-10257](https://github.com/spring-projects/spring-framework/issues/14890) |

| Bean Validation / Hibernate Validator: simplify Maven dependencies and backward compatibility |[HV-790](https://hibernate.atlassian.net/browse/HV-790) and [HV-792](https://hibernate.atlassian.net/browse/HV-792) |

| Spring Data: provide more flexibility when working with JPQL queries | [DATAJPA-292](https://github.com/spring-projects/spring-data-jpa/issues/704) |



## Contributing



The [issue tracker](https://github.com/spring-petclinic/spring-petclinic-jooq/issues) is the preferred channel for bug reports, feature requests and submitting pull requests.



For pull requests, editor preferences are available in the [editor config](.editorconfig) for easy use in common text editors. Read more and download plugins at . All commits must include a __Signed-off-by__ trailer at the end of each commit message to indicate that the contributor agrees to the Developer Certificate of Origin.

For additional details, please refer to the blog post [Hello DCO, Goodbye CLA: Simplifying Contributions to Spring](https://spring.io/blog/2025/01/06/hello-dco-goodbye-cla-simplifying-contributions-to-spring).



## License



The Spring PetClinic sample application is released under version 2.0 of the [Apache License](https://www.apache.org/licenses/LICENSE-2.0).