MyBatis-Plus streamliens service creation by extending the IService interface. Begin by declaring a role service contract:

public interface ISysRoleService extends IService<SysRole> {
}

The default implemantation uses ServiceImpl, which handles dependency injection of the maper:

@Service
public class SysRoleService extends ServiceImpl<SysRoleMapper, SysRole> implements ISysRoleService {
    // The baseMapper field is auto-wired from the Mapper interface provided in the type parameters.
}

With the service in place, create a test class to verify operations:

@SpringBootTest
public class RoleServiceTest {
    @Autowired
    private ISysRoleService roleService;
}

Fetching all roles

@Test
void testRetrieveAll() {
    List<SysRole> roles = roleService.list();
    roles.forEach(System.out::println);
}

Adding a new role

@Test
void testAddRole() {
    SysRole role = new SysRole();
    role.setRoleName("Administrator");
    role.setRoleCode("admin");
    role.setDescription("Full system access role");
    boolean saved = roleService.save(role);
    System.out.println(saved);
    System.out.println(role);
}

Modifying a role's code

@Test
void testModifyRoleCode() {
    SysRole role = new SysRole();
    role.setId(20L);
    role.setRoleCode("supervisor");
    boolean updated = roleService.updateById(role);
    System.out.println(updated);
}

Deleting a role by ID

@Test
void testRemoveRole() {
    boolean removed = roleService.removeById(25);
    System.out.println(removed);
}

Batch deletion

@Test
void testBatchRemove() {
    boolean result = roleService.removeByIds(Arrays.asList(3, 8));
    System.out.println(result);
}

Conditional querying with LambdaQueryWrapper

@Test
void testQueryByCondition() {
    LambdaQueryWrapper<SysRole> lambdaQuery = new LambdaQueryWrapper<>();
    lambdaQuery.eq(SysRole::getRoleCode, "supervisor");
    List<SysRole> roles = roleService.list(lambdaQuery);
    roles.forEach(System.out::println);
}

Note: When using @MapperScan, ensure the base package points exactly to the mapper package (not a parent package) to prevent scanning conflicts and startup errors.