Mocking object from another class - junit

Question

I have a service class that starts a service.
This service should only start between a certain time.
So i need to mock this , but it does not work.
My Time class:
public boolean isTimeBetween_00_06(){
return Instant.now().isBefore(Instant.now()
.truncatedTo(ChronoUnit.DAYS)
.plus(6,ChronoUnit.HOURS));
}
My Service class:
start(){
if(! new MyTimeUtils().isTimeBetween_00_06){
throw new Exception;
}
}
My test class:
#InjectMocks
private MyServiceClass service;
#Mock
private MyTimeUtils myTimeUtils;
#Test
myTest(){
Mockito.when(myTimeUtils.isCurrentTimeBetween_00_06()).thenReturn(true);
service.start();
}
I expect that I get the right assert, but it stops with Exption.
I also tryed PowerMockito but still it did not work.
Someone have an idea?
Best Regards.

Answer 1

You should inject MyTimeUtils instead of instance creation in the method.
And don't forget #RunWith(MockitoJUnitRunner.class);
Have a look at the code, please:
public class MyServiceClass {
private final MyTimeUtils myTimeUtils;
public MyServiceClass(MyTimeUtils myTimeUtils) {
this.myTimeUtils = myTimeUtils;
}
public void start() {
if (!myTimeUtils.isTimeBetween_00_06()) {
throw new IllegalStateException("ERROR");
}
}
}
#RunWith(MockitoJUnitRunner.class)
public class MyServiceClassTest {
#InjectMocks
private MyServiceClass service;
#Mock
private MyTimeUtils myTimeUtils;
#Test
public void myTest(){
Mockito.when(myTimeUtils.isTimeBetween_00_06()).thenReturn(true);
service.start();
}
}