ExampleService

This Java class is a Service called ExampleService that extends DefaultAssemblingEntityService. A Service in Spring is a class that holds business logic and calls methods in the repositories to interact with the database. It sits between the controllers and the repositories. Let’s breakdown the important sections of the code.

• @Service: This is a Spring stereotype annotation that is used at the class level. It indicates that the class holds the business logic in Service methods.

@Service
public class ExampleService
    extends DefaultAssemblingEntityService<ExampleEntity, ExampleEntityDto, ExampleRepresentation> {
 
  protected ExampleService(@NotNull ExampleRepository repository, ExampleAssembler assembler) {
    super(repository, assembler);
  }
 
  @Override
  protected @NotNull <E extends ExampleEntityDto> ExampleEntity convertDtoToEntity(
      @NotNull E entity) {
    return ExampleEntity.builder().id(entity.getId()).content(entity.getContent()).build();
  }
}

The ExampleService class extends the DefaultAssemblingEntityService class, which likely contains common service layer operations for ExampleEntity objects.

The ExampleService constructor takes an instance of ExampleRepository and ExampleAssembler and passes them to the superclass’ constructor. This represents dependency injection, where the repository and assembler instances are supplied to the service, typically by the Spring framework itself.

The convertDtoToEntity method is overridden from DefaultAssemblingEntityService. It converts an ExampleEntityDto object to an ExampleEntity object, which can then be saved to the database or processed further.