Why is there a NPE on #Injectable class - jmockit

Question

I have a class(looks something like this) I'm trying to test.
#Component
#Path("/user")
#Produces(MediaType.APPLICATION_JSON)
public class UserResource extends BaseResource {
#Autowired UserService userService;
#POST
#Path("register")
public User registerUser(User user){
...
User registeredUser = userService.register(user);
...
return registeredUser;
}
}
The test looks like this.
public class UserResourceTest {
#Tested UserResource userResource;
#Injectable UserService userService;
#Mocked BaseResource baseResource;
#Test
public void registerShouldDoSomething(){
User user = new User();
final User registerResult = new User();
...
new NonStrictExpectations() {{
userService.register((User)any); result = registerResult;
}};
userResource.registerUser(user);
...
}
}
For some reason in the tested class, userService is null and throwing a NPE when register is called on it (UserService is a class not interface/abstract btw). I'm wondering if perhaps some of the annotations(javax or Spring) may be clashing with JMockit or something(Although I've tried removing them)?
I've tried switching the injectable to just #Mocked, and I've tried removing it and having it be a #Mocked test method param. Nothing seems to be solving the NPE.

Answer 1

I had the same issue, the problem was mixing Spring annotations - Autowired with Java Resource. If you mix them only Java will be injected.
For more details please take a look at:
mockit.internal.expectations.injection.InjectionPoint
mockit.internal.expectations.injection.FieldInjection
especially discardFieldsNotAnnotatedWithJavaxInjectIfAtLeastOneIsAnnotated method.
This is a dirty solution to the problem:
package mockit.internal.expectations.injection;
import java.lang.reflect.Field;
import java.lang.reflect.Modifier;
public class DirtyHack {
static {
try {
setFinalStatic(InjectionPoint.class.getDeclaredField("WITH_INJECTION_API_IN_CLASSPATH"), false);
} catch (Exception e) {
e.printStackTrace();
}
}
static void setFinalStatic(Field field, Object newValue) throws Exception {
field.setAccessible(true);
Field modifiersField = Field.class.getDeclaredField("modifiers");
modifiersField.setAccessible(true);
modifiersField.setInt(field, field.getModifiers() & ~Modifier.FINAL);
field.set(null, newValue);
}
}
Then your test need to for example extends this class.

Answer 2

I ended up using reflection to manually set the #Injectable fields in the #Tested class
public class UserResourceTest {
#Tested UserResource userResource;
#Injectable UserService userService;
#Mocked BaseResource baseResource;
#Test
public void registerShouldDoSomething(){
Deencapsulation.setField(userResource,userService); //This line
User user = new User();
final User registerResult = new User();
...
new NonStrictExpectations() {{
userService.register((User)any); result = registerResult;
}};
userResource.registerUser(user);
...
}
}
Still not sure what the bug is, but this works for me