spring-petclinic

A sample Spring-based application

7,900

24,279

7,900

View on GitHub

Top Related Projects

spring-boot-admin

12,442

Admin UI for administration of spring boot applications

generator-jhipster

21,699

JHipster is a development platform to quickly generate, develop, & deploy modern web applications & microservice architectures.

spring-boot

75,856

Spring Boot helps you to create Spring-powered, production-grade applications and services with absolute minimum fuss.

quarkus

13,990

Quarkus: Supersonic Subatomic Java.

Quick Overview

Spring PetClinic is a sample application designed to demonstrate the capabilities of the Spring Framework. It's a simple yet functional pet clinic management system that showcases various Spring technologies, including Spring Boot, Spring MVC, Spring Data JPA, and Thymeleaf.

Pros

Excellent learning resource for Spring Framework beginners
Demonstrates best practices in Spring application development
Regularly updated to incorporate the latest Spring technologies
Well-documented and easy to understand codebase

Cons

Limited in scope and functionality as a sample application
May not cover all advanced Spring features
Not intended for production use without significant modifications
Could be overwhelming for absolute beginners due to the use of multiple Spring technologies

Code Examples

Defining a JPA Entity:

@Entity
@Table(name = "owners")
public class Owner extends Person {

    @Column(name = "address")
    @NotEmpty
    private String address;

    @Column(name = "city")
    @NotEmpty
    private String city;

    @Column(name = "telephone")
    @NotEmpty
    @Digits(fraction = 0, integer = 10)
    private String telephone;

    @OneToMany(cascade = CascadeType.ALL, mappedBy = "owner")
    private Set<Pet> pets;

    // Getters and setters
}

Creating a Spring MVC Controller:

@Controller
class OwnerController {

    private static final String VIEWS_OWNER_CREATE_OR_UPDATE_FORM = "owners/createOrUpdateOwnerForm";

    private final OwnerRepository owners;

    public OwnerController(OwnerRepository clinicService) {
        this.owners = clinicService;
    }

    @GetMapping("/owners/new")
    public String initCreationForm(Map<String, Object> model) {
        Owner owner = new Owner();
        model.put("owner", owner);
        return VIEWS_OWNER_CREATE_OR_UPDATE_FORM;
    }

    @PostMapping("/owners/new")
    public String processCreationForm(@Valid Owner owner, BindingResult result) {
        if (result.hasErrors()) {
            return VIEWS_OWNER_CREATE_OR_UPDATE_FORM;
        }
        else {
            this.owners.save(owner);
            return "redirect:/owners/" + owner.getId();
        }
    }
}

Configuring Spring Data JPA Repository:

@Repository
public interface OwnerRepository extends Repository<Owner, Integer> {

    @Query("SELECT DISTINCT owner FROM Owner owner left join fetch owner.pets WHERE owner.lastName LIKE :lastName%")
    @Transactional(readOnly = true)
    Collection<Owner> findByLastName(@Param("lastName") String lastName);

    @Query("SELECT owner FROM Owner owner left join fetch owner.pets WHERE owner.id =:id")
    @Transactional(readOnly = true)
    Owner findById(@Param("id") Integer id);

    void save(Owner owner);
}

Getting Started

To run the Spring PetClinic application:

Clone the repository:

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

Navigate to the project directory:
```
cd spring-petclinic
```
Run the application using Maven:
```
./mvnw spring-boot:run
```
Access the application in your web browser at http://localhost:8080

Competitor Comparisons

spring-boot-admin

12,442

Admin UI for administration of spring boot applications

Pros of Spring Boot Admin

Provides a comprehensive UI for monitoring and managing Spring Boot applications
Offers advanced features like log file access, JMX bean management, and metrics visualization
Supports multiple Spring Boot applications in a single dashboard

Cons of Spring Boot Admin

More complex setup compared to Spring PetClinic's straightforward structure
Requires additional configuration and dependencies for full functionality
May introduce overhead in smaller projects or development environments

Code Comparison

Spring Boot Admin (application.properties):

spring.boot.admin.client.url=http://localhost:8080
management.endpoints.web.exposure.include=*
management.endpoint.health.show-details=always

Spring PetClinic (application.properties):

spring.datasource.url=jdbc:h2:mem:testdb
spring.jpa.hibernate.ddl-auto=update
logging.level.org.springframework=INFO

Spring Boot Admin focuses on monitoring and management configuration, while Spring PetClinic emphasizes database and application-specific settings. The Spring Boot Admin example shows client configuration for connecting to the admin server and exposing management endpoints, whereas Spring PetClinic's configuration is centered around database connection and basic application properties.

generator-jhipster

21,699

JHipster is a development platform to quickly generate, develop, & deploy modern web applications & microservice architectures.

Pros of generator-jhipster

Generates a complete, production-ready application with various technology options
Supports multiple front-end frameworks and database types
Offers continuous integration setup and deployment options out-of-the-box

Cons of generator-jhipster

Steeper learning curve due to its extensive feature set
Generated code can be complex and may require more effort to customize
Larger initial project size, which may be overkill for simple applications

Code Comparison

spring-petclinic (Java):

@GetMapping("/owners/{ownerId}")
public ModelAndView showOwner(@PathVariable("ownerId") int ownerId) {
    ModelAndView mav = new ModelAndView("owners/ownerDetails");
    mav.addObject(this.owners.findById(ownerId));
    return mav;
}

generator-jhipster (TypeScript):

@Get('users/:id')
getUser(@Param('id') id: string): Promise<User> {
    return this.userService.findById(id);
}

The spring-petclinic example shows a simple controller method returning a ModelAndView object, while the generator-jhipster example demonstrates a more modern, REST-style approach using TypeScript and decorators. This reflects the differences in architecture and technology choices between the two projects.

spring-boot

75,856

Spring Boot helps you to create Spring-powered, production-grade applications and services with absolute minimum fuss.

Pros of Spring Boot

More comprehensive framework for building production-ready applications
Provides auto-configuration and starter dependencies for easier setup
Offers a wide range of features beyond basic web applications

Cons of Spring Boot

Steeper learning curve for beginners due to its extensive feature set
Potentially more complex configuration for simple applications
Larger footprint and potentially slower startup times

Code Comparison

Spring Boot application entry point:

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

Spring PetClinic main configuration:

@Configuration
@EnableWebMvc
@ComponentScan("org.springframework.samples.petclinic")
public class WebConfig implements WebMvcConfigurer {
    // Configuration details
}

Spring Boot focuses on simplifying the setup process with annotations and auto-configuration, while Spring PetClinic demonstrates a more traditional Spring MVC setup. Spring Boot's approach reduces boilerplate code and streamlines development, but may abstract away some details that are more explicit in the PetClinic example.

micronaut-core

6,119

Micronaut Application Framework

Pros of Micronaut Core

Faster startup time and lower memory footprint due to compile-time dependency injection
Built-in support for cloud-native features and microservices architecture
Extensive support for reactive programming and non-blocking I/O

Cons of Micronaut Core

Smaller community and ecosystem compared to Spring
Steeper learning curve for developers familiar with traditional Java frameworks
Less comprehensive documentation and fewer third-party integrations

Code Comparison

Spring PetClinic:

@Controller
class OwnerController {
    private final OwnerRepository owners;

    public OwnerController(OwnerRepository clinicService) {
        this.owners = clinicService;
    }
}

Micronaut Core:

@Controller("/owners")
public class OwnerController {
    private final OwnerRepository owners;

    public OwnerController(OwnerRepository owners) {
        this.owners = owners;
    }
}

Both examples show similar controller implementations, but Micronaut uses compile-time annotation processing for dependency injection, while Spring relies on runtime reflection. This difference contributes to Micronaut's faster startup times and reduced memory usage.

quarkus

13,990

Quarkus: Supersonic Subatomic Java.

Pros of Quarkus

Faster startup time and lower memory footprint
Native compilation support for improved performance
Reactive programming model with built-in support for event-driven architectures

Cons of Quarkus

Smaller ecosystem and community compared to Spring
Steeper learning curve for developers familiar with traditional Java frameworks
Limited support for legacy Java EE applications

Code Comparison

Spring PetClinic:

@GetMapping("/owners/{ownerId}")
public ModelAndView showOwner(@PathVariable("ownerId") int ownerId) {
    ModelAndView mav = new ModelAndView("owners/ownerDetails");
    mav.addObject(this.owners.findById(ownerId));
    return mav;
}

Quarkus:

@GET
@Path("/owners/{ownerId}")
@Produces(MediaType.APPLICATION_JSON)
public Owner getOwner(@PathParam("ownerId") Long ownerId) {
    return Owner.findById(ownerId);
}

The Quarkus example demonstrates a more concise approach using JAX-RS annotations, while Spring PetClinic uses Spring MVC annotations and returns a ModelAndView object. Quarkus focuses on RESTful APIs, whereas Spring PetClinic includes view-related logic in the controller.

Convert designs to code with AI

Introducing Visual Copilot: A new AI model to turn Figma designs to high quality code using your components.

Try Visual Copilot

README

Spring PetClinic Sample Application

Understanding the Spring Petclinic application with a few diagrams

See the presentation here

Run Petclinic locally

Spring Petclinic is a Spring Boot application built using Maven or 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):

git clone https://github.com/spring-projects/spring-petclinic.git
cd spring-petclinic
./mvnw package
java -jar target/*.jar

You can then access the Petclinic at http://localhost:8080/.

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):

./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:

./mvnw spring-boot:build-image

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

Our issue tracker is available here.

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:<uuid> 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 for more detail on how to set the active profile.

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

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

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 and PostgreSQL.

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:

docker compose up mysql

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 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
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
- Spring Tools Suite (STS)
- IntelliJ IDEA
- VS Code

Steps

On the command line run:

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

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.
Inside IntelliJ IDEA:

In the main menu, chooseÂ File -> Open and select theÂ Petclinic 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'.
Navigate to the Petclinic

Visit http://localhost:8080 in your browser.

Looking for something in particular?

Spring Boot Configuration	Class or Java property files
The Main Class	PetClinicApplication
Properties Files	application.properties
Caching	CacheConfiguration

Interesting Spring Petclinic branches and forks

The Spring Petclinic "main" branch in the spring-projects GitHub org is the "canonical" implementation based on Spring Boot and Thymeleaf. There are quite a few forks in the GitHub org 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 and SPR-10257
Bean Validation / Hibernate Validator: simplify Maven dependencies and backward compatibility	HV-790 and HV-792
Spring Data: provide more flexibility when working with JPQL queries	DATAJPA-292

Contributing

The issue tracker is the preferred channel for bug reports, feature requests and submitting pull requests.

For pull requests, editor preferences are available in the editor config for easy use in common text editors. Read more and download plugins at https://editorconfig.org. If you have not previously done so, please fill out and submit the Contributor License Agreement.

License

The Spring PetClinic sample application is released under version 2.0 of the Apache License.

Top Related Projects

Convert designs to code with AI

Introducing Visual Copilot: A new AI model to turn Figma designs to high quality code using your components.

Try Visual Copilot