My First Full Stack Spring Boot / JQuery Application

Part 2 - Creating a Repository / Config

Create Repository

• Data Access Objects (DAOs) provide an abstraction for interacting with datastores.
• In the Spring framework, repositories act as a specific type of DAO which can access a respective database table.
  • For example, PersonRepository can access a respective PERSON database table.
• Typically DAOs include an interface that provides
  1. a set of finder methods for retrieving data such as readById, readAll
  2. and methods to persist and delete data such as create, updateById, and deleteById
• It is customary to have one Repository per model object.

public interface PersonRepository extends CrudRepository<Person, Long> {
}

Prepopulate The Entity

• Populates the Person table in H2 with entities before the Web Server begins serving.

@Configuration
public class PersonConfig {
    @Autowired
    private PersonRepository repository;

    @PostConstruct
    public void setup() {
        Person person1 = new Person();
        person1.setFirstName("Leon");
        person1.setLastName("Hunter");

        Person person2 = new Person();
        person2.setFirstName("John");
        person2.setLastName("Doe");

        repository.saveAll(Arrays.asList(
                person1,
                person2
        ));
    }
}

• View the newly added records by
  1. restarting the application
  2. navigating to localhost:8080/h2-console
  3. Executing query SELECT * FROM PERSON in the H2-Console