#MockBean-instance used via #Autowire before method injection - spring-boot

Question

In my JUNIT5-test I want to mock a bean by #MockBean. In my #BeforeEach - method the calls are injected.
But other beans #Autowire-ing the #MockBean are instantiated with the #MockBean before the method injection. This is weird and gives me NPEs. How can I force method injection before use of the #MockBean?
#SpringBootTest
#ExtendWith(SpringExtension.class)
#ContextConfiguration("classpath:context/authenticationStaff.xml")
#EnableAutoConfiguration
public class PasswordPolicyServiceTest {
private final List<Reference> bcryptDigestRefs = new ArrayList<>();
private final DigestHistoryRule bcryptDigestRule = new DigestHistoryRule(new BCryptHashBean());
#MockBean
private SystemConfiguration systemConfiguration;
#BeforeEach
public void initMock() {
MockitoAnnotations.initMocks(this);
Arrays.asList(SystemConfigKey.values()).forEach(key -> {
Mockito.when(systemConfiguration.getConfig(key)).thenReturn(getConfig(key, key.getDefaultValue()));
});
Mockito.when(systemConfiguration.getConfig(SystemConfigKey.MIN_PASSWORD_LENGTH)).thenReturn(getConfig(SystemConfigKey.MIN_PASSWORD_LENGTH, "5"));
A failing class is:
#Service
public class SessionCacheManager {
private final Ehcache ehCache;
private final Cache<String, SessionVerificationType> sessionCache;
private final SystemConfiguration systemConfiguration;
#Autowired
public SessionCacheManager(final Ehcache ehCache, final SystemConfiguration systemConfiguration) {
this.ehCache=ehCache;
this.systemConfiguration=systemConfiguration;
SystemConfigType systemConfig = systemConfiguration.getConfig(SystemConfigKey.SESSION_MAX_NUMBER);
Integer numberOfParalledSessions = systemConfig.getIntegerValue();
CacheManager cacheManager=ehCache.registerNewCacheManager(CACHE_MANAGER);
sessionCache = cacheManager.createCache(CACHE_NAME,
CacheConfigurationBuilder.newCacheConfigurationBuilder(String.class, SessionVerificationType.class, ResourcePoolsBuilder.heap(numberOfParalledSessions)));
}
As I can see (with debug), the "SessionCacheManager" uses the mocked "SystemConfiguration" but systemConfiguration.getConfig(SystemConfigKey.SESSION_MAX_NUMBER); returns a null.

Answer 1

I helped myself, though I do not like my solution. It is more a trick than a solution. But I cannot think of something else right now.
I change the #ContextConfiguration to:
#ContextConfiguration(locations = "/context/authenticationStaff.xml", classes = { SpringApplicationContext.class })
The XML is setup, that it cannot autodetect the class "SystemConfiguration.class".
Instead of that the "SpringApplicationContext.class" provides the "SystemConfiguration.class" as a mocked bean.
#Configuration
public class SpringApplicationContext {
#Mock
private SystemConfiguration mockedSystemConfiguration;
#Bean
public SystemConfiguration systemConfiguration() {
MockitoAnnotations.initMocks(this);
Arrays.asList(SystemConfigKey.values()).forEach(key -> {
Mockito.when(mockedSystemConfiguration.getConfig(key)).thenReturn(getConfig(key, key.getDefaultValue()));
});
Mockito.when(mockedSystemConfiguration.getConfig(SystemConfigKey.MIN_PASSWORD_LENGTH)).thenReturn(getConfig(SystemConfigKey.MIN_PASSWORD_LENGTH, "5"));
Mockito.when(mockedSystemConfiguration.getConfig(SystemConfigKey.PASSWORD_BCRYPTENCODER_COSTFACTOR)).thenReturn(getConfig(SystemConfigKey.PASSWORD_BCRYPTENCODER_COSTFACTOR, "5"));
return mockedSystemConfiguration;
}
private SystemConfigType getConfig(SystemConfigKey key, String value) {
SystemConfigType config = new SystemConfigType();
config.setKey(key);
config.setValue(value);
return config;
}
The test-code now looks like this:
#SpringBootTest
#ExtendWith(SpringExtension.class)
#ContextConfiguration(locations = "/context/authenticationStaff.xml", classes = { SpringApplicationContext.class })
#EnableAutoConfiguration
public class PasswordPolicyServiceTest {
#Autowired
private PasswordPolicyService passwordPolicyService;
#Autowired
private PasswordHandlerService passwordHandlerService;
#Autowired
private SystemConfiguration systemConfiguration;
private final List<Reference> bcryptDigestRefs = new ArrayList<>();
private final DigestHistoryRule bcryptDigestRule = new DigestHistoryRule(new BCryptHashBean());
#BeforeEach
public void initMock() {
MockitoAnnotations.initMocks(this);
String password=passwordHandlerService.getPassword("my$Password");
bcryptDigestRefs.add(
new HistoricalReference(
"bcrypt-history",
password));
}
This works, but is not a nice solution. Other recommendations are very welcome.