Cannot instantiate class DataAccess because of mocking DB mapper in unit test

Question

Getting errors for trying to test my data access class:

Cause: org.apache.ibatis.builder.BuilderException: Error parsing SQL Mapper Configuration. Cause: org.apache.ibatis.datasource.DataSourceException

Test class:

@Tested
DataAccess dataAccess;

@Mock
Mapper mapper;

DataAccess class:

private Logger logger;

private final Mapper mapper;

public DataAccess() {
    String loggerCategory = new properties().getLoggerCategory();
    logger = LoggerFactory.getLogger(loggerCategory);

    mapper = DBControl.getAutoClosingMapper(
            Mapper.class, DataSource.source, logger);
}

DBControl (where the error is coming from):

private static final SqlSessionFactory sqlMapper;

static {
   Reader reader = null;
   String resource = "configuration.database.xml";
   reader = Resources.getResourceAsReader(resource);

   //the exception is getting thrown from this line
   sqlMapper = new SqlSessionFactoryBuilder().build(reader);
}

I've tried several different mockito and jmockit annotations in my test class but I am left with the same error each time.

I simply just need to mock the mapper.

Answer 1

One thing that I noticed here, is that you are using the @Mock annotation to try to mock a final class variable, that typically is not going to work unless you have a constructor someplace.

e.g.

public class DataAccess{

   private final Mapper mapper;
   DataAccess(mapper){
    this.mapper = mapper
    // anything else
   }
}

Using mockito you could do something like this:

public class TestClass{
 private DataAccess dataAccess = new DataAccess(Mockito.mock(Mapper.class));
}

Also, I would typically instantiate the Logger when you declare it;

private final Logger LOGGER = LoggerFactory.getLogger(getClass());