Spring Boot Integration Tests, #Autowired works, #Inject does not, Why? - spring-boot

Question

I work on a Spring Boot application, I have written a Service and I want to test this Service in an Integration Test. Therefor I want to Inject the Service Into my test. If I use the #Inject annotation, The Service is null. If I use #Autowired, the Service gets Injected and the test works. I thought the annotation should do more or less the same, with the only differrence that #Autowired fails if no bean is available, because it is default set to required=true.The Service has an Interface and I choose the implementation based on Field Name.
Interface:
import org.springframework.core.io.ByteArrayResource;
import java.io.IOException;
import java.io.InputStream;
import java.util.Optional;
public interface FileService {
boolean storeDicomZip(InputStream stream, long caseId);
.
.
.
}
Implementation:
import org.apache.commons.io.FileUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.core.io.ByteArrayResource;
import org.springframework.core.io.ClassPathResource;
import org.springframework.stereotype.Service;
import org.springframework.util.FileCopyUtils;
import java.io.*;
import java.nio.file.Files;
import java.util.Optional;
#Service
public class FileSystemFileService implements FileService {
.
.
.
}
And The Test:
import org.junit.Assert;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.IntegrationTest;
import org.springframework.boot.test.SpringApplicationConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
import org.springframework.test.context.web.WebAppConfiguration;
import java.io.ByteArrayInputStream;
import java.io.InputStream;
#RunWith(SpringJUnit4ClassRunner.class)
#SpringApplicationConfiguration(classes = Application.class)
#WebAppConfiguration
#IntegrationTest
public class FileSystemFileServiceTest {
#Autowired
private FileService fileSystemFileService;
#Test
public void storeDicomZip() throws Exception {
InputStream stream = new ByteArrayInputStream("TEST".getBytes());
fileSystemFileService.storeDicomZip(stream, 3);
Assert.assertTrue(fileSystemFileService.getDicomZipVersions(3) == 1);
}
.
.
.
}
As described, If I use #Autowired, like here it works, if I use #Inject it does not because fileSystemFileService is null.
Does somebody know why this is the case, and what I have to change to use #Inject?