Multi-Tenant Applications in Spring Boot with H2 Database

November 06, 2025

#1

This guide shows how to create multi-tenant applications in Spring Boot using H2 database for simple testing and development.

1. Add Dependencies

<dependency>
  <groupId>org.springframework.boot</groupId>
  <artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<dependency>
  <groupId>com.h2database</groupId>
  <artifactId>h2</artifactId>
</dependency>

2. Configure H2 Database

spring.datasource.url=jdbc:h2:mem:tenantdb
spring.datasource.driver-class-name=org.h2.Driver
spring.jpa.hibernate.ddl-auto=create
spring.h2.console.enabled=true

3. Tenant Aware Entity

@Entity
public class Customer {
  @Id @GeneratedValue
  private Long id;
  private String name;
  private String tenantId;
}

4. Repository with Tenant Filter

public interface CustomerRepository extends JpaRepository<Customer, Long> {
  List<Customer> findByTenantId(String tenantId);
}

5. Service Layer

@Service
public class CustomerService {
  private final CustomerRepository repo;

  public CustomerService(CustomerRepository repo) {
    this.repo = repo;
  }

  public Customer save(String tenantId, String name) {
    return repo.save(new Customer(null, name, tenantId));
  }

  public List<Customer> findAll(String tenantId) {
    return repo.findByTenantId(tenantId);
  }
}

6. REST Controller

@RestController
@RequestMapping("/customers")
public class CustomerController {
  private final CustomerService service;

  public CustomerController(CustomerService service) {
    this.service = service;
  }

  @PostMapping("/{tenantId}")
  public Customer add(@PathVariable String tenantId, @RequestBody String name) {
    return service.save(tenantId, name);
  }

  @GetMapping("/{tenantId}")
  public List<Customer> get(@PathVariable String tenantId) {
    return service.findAll(tenantId);
  }
}