Cannot instantiate @InjectMocks field named exception with java class

if you do a employee = new Employee(param1, param2); you may as well skip @InjectMocks.

It is supposed to do the following:

@InjectMocks
ClassUnderTest cut;

@Mock
Dependency1 dep1;
@Mock
Dependency2 dep2;

@Before
public void setup() {
  initMocks(this);
}

omitting @InjectMocks the same behaviour can be achieved with the following code:

ClassUnderTest cut;

@Mock
Dependency1 dep1;
@Mock
Dependency2 dep2;

@Before
public void setup() {
  initMocks(this);
  cut = new ClassUnderTest(dep1, dep2);
}

In your specific case, you should mock param1 and param2. Never call the constructor manually when using @InjectMocks.