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ArgumentCaptor captures wrong class

SOLVED: Even if the getValue() on the Argument Captor shows you this, it is normal. To be honest I was expecting to see and instance on the OnLoginWithEmailCallback interface here. The problem on my side was related to a method call on mView which was generating a NPE. Works like a charm now.
ORIGINAL PROBLEM:
I am implementing my first unit test using Mockito in my MVP app and I need to mock the behaviour of a callback when the user is logging in. I am using Firebase to handle the authentication.
I followed a very good tutorial from here : https://fernandocejas.com/2014/04/08/unit-testing-asynchronous-methods-with-mockito/.
I am calling method on class under test. This method calls another one on the Auth Presenter which does the actual work
mPresenter.performLoginWithEmail(EMAIL, PASSWORD);
Then I am verifying that an underlining method in the Auth Presenter class was called. I try to capture the callback interface.
verify(mAuthPresenter, times(1)).login(mOnLoginWithEmailCallbackArgumentCaptor.capture(),
eq(EMAIL), eq(PASSWORD));
The problem is that getValue() from the Argument Captor returns an instance of the mPresenter (class under test) instead of the OnLoginWithEmailCallback interface class. Therefore I get an NPE.
mOnLoginWithEmailCallbackArgumentCaptor.getValue().onLoginWithEmailSuccess();
Here is the complete test class:
#RunWith(MockitoJUnitRunner.class)
public class LoginPresenterTest {
private static String EMAIL = "test#rmail.com";
private static String PASSWORD = "1234";
//class under test
private LoginPresenter mPresenter;
#Mock
AuthPresenter mAuthPresenter;
#Captor
private ArgumentCaptor<OnLoginWithEmailCallback> mOnLoginWithEmailCallbackArgumentCaptor;
#Mock
ILoginActivityView mView;
#Before
public void setupLoginPresenter() {
MockitoAnnotations.initMocks(this);
// Get a reference to the class under test
mPresenter = new LoginPresenter(mView, mAuthPresenter);
}
#Test
public void performLoginWithEmail() {
mPresenter.performLoginWithEmail(EMAIL, PASSWORD);
//wanting to have control over the callback object. therefore call capture to then call methods on the interface
verify(mAuthPresenter, times(1)).login(mOnLoginWithEmailCallbackArgumentCaptor.capture(),
eq(EMAIL), eq(PASSWORD));
mOnLoginWithEmailCallbackArgumentCaptor.getValue().onLoginWithEmailSuccess();
InOrder inOrder = Mockito.inOrder(mView);
inOrder.verify(mView).goToMap();
inOrder.verify(mView).hideProgressBar();
}
}
EDIT: This is the call to mAuthPresenter.login:
SOLVED: getLoginActivityView() was causing an NPE
public void performLoginWithEmail(String email, String password) {
mAuthPresenter.login(new OnLoginWithEmailCallback() {
#Override
public void onLoginWithEmailSuccess() {
getLoginActivityView().goToMap();
getLoginActivityView().hideProgressBar();
}
#Override
public void onLoginWithEmailFailed(String error) {
getLoginActivityView().hideProgressBar();
getLoginActivityView().showToast(error);
}
}, email, password);
}
I also tried using using doAnswer from Mockito:
doAnswer(new Answer() {
#Override
public Object answer(InvocationOnMock invocation) throws Throwable {
((OnLoginWithEmailCallback)invocation.getArguments()[0]).onLoginWithEmailSuccess();
return null;
}
}).when(mAuthPresenter).login(
any(OnLoginWithEmailCallback.class, EMAIL, PASSWORD));
Still, invocation.getArguments() return an instance of the class under test (LoginPresenter), so the same problem as before. Can you help me?

The problem was that i got confused by the Argument Captor which returned me an instance of the caller class (LoginPresenter). The problem in my case was with a method inside the anonymouse class OnLoginWithEmailCallback() which was throwing an NPE.

How to mock Callback answer for static methods with PowerMock?

I need to mock some static methods, that's fine so far and can be done like this:
#RunWith(PowerMockRunner.class)
#PrepareForTest({DataService.class})
public class PlayersAllViewModelTest {
// mock objects
private PlayersAllContextHandler mContextHandler;
private PlayersAllAdapter mAdapter;
#Before
public void setUp() throws Exception {
mockStatic(DataService.class);
//define mocks
mContextHandler = mock(PlayersAllContextHandler.class);
mAdapter = mock(PlayersAllAdapter.class);
}
#Test
public void check_init_requests_are_done() throws Exception {
// create instance of viewmodel
new PlayersAllViewModel(mContextHandler, mAdapter);
// check dataservice is requested for method 'getAllPlayers()'
PowerMockito.verifyStatic();
DataService.getAllPlayers(any(DataServiceCallback.class));
}
I need to test the behavior for a given response (success() / failure()) answered in a callback. The normal way to do so is like this:
// define mock answer
doAnswer(new Answer<MyCallback<String>>() {
#Override
public MyCallback answer(InvocationOnMock invocation) throws Throwable {
MyCallback<Player> callback = (MyCallback<Player>) invocation.getArguments()[0];
callback.onFailure(new UnsupportedOperationException());
return null;
}
}).when(>>mocked class instance<<).myTestMethod(any(MyCallback.class));
Because is want to call a static method, i can't do it like that so. There's no mocked instance of a class that could fill the gap :(
Does anybody know what's the correct way to do it?

How to get the activity reference before its oncreate gets called during testing

How to get the reference of Activity before its onCreate will be called. while its under test. I use ActivityTestRule as JUnit Rule. The reason for this requirement is i want to inject Mocks into activity from tests.
public class MyActivity extends Activity{
MyComponent myComponent;
#Override
public void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
if(myComponent==null){
myComponent ... //initialise dagger component
}
myComponent.inject(this);
...
}
public void setComponent(MyComponent comp){
this.myComponent = comp;
}
}
public class MyTest{
#Rule
public ActivityTestRule<MyActivity> intentsTestRule = new ActivityTestRule<>(MyActivity.class);
MyComponent myFakeComponent;
#Before
public void setUp() {
MyActivity activity = intentsTestRule.getActivity();
activity.setComponent(myFakeComponent);
}
#Test
public void testMethod1(){...}
}

As per documentation, what you're doing here is wrong.
#Rule
public ActivityTestRule<MyActivity> intentsTestRule = new ActivityTestRule<>(MyActivity.class);
MyComponent myFakeComponent;
#Before
public void setUp() {
MyActivity activity = intentsTestRule.getActivity();
activity.setComponent(myFakeComponent);
}
Because,
This rule provides functional testing of a single activity.
The activity under test will be launched before each test annotated with
Test and before methods annotated with #Before.
It will be terminated after the test is completed and methods
annotated with After are finished. During the duration of the test
you will be able to manipulate your Activity directly.
However!
protected void beforeActivityLaunched ()
Override this method to execute any code that should run
before your Activity is created and launched.
This method is called before each test method,
including any method annotated with #Before.
Therefore, if you move the initialization of the MainActivityComponent outside the Activity to a place that is mockable, then you'll be able to tinker it together before the main activity is created.
EDIT:
Another possible solution is to lazily initiate the Activity as per link.
#Rule
public ActivityTestRule<NoteDetailActivity> mNoteDetailActivityTestRule =
new ActivityTestRule<>(NoteDetailActivity.class, true /* Initial touch mode */,
false /* Lazily launch activity */);
#Before
public void intentWithStubbedNoteId() {
// Add a note stub to the fake service api layer.
FakeNotesServiceApiImpl.addNotes(NOTE);
// Lazily start the Activity from the ActivityTestRule this time to inject the start Intent
Intent startIntent = new Intent();
startIntent.putExtra(NoteDetailActivity.EXTRA_NOTE_ID, NOTE.getId());
mNoteDetailActivityTestRule.launchActivity(startIntent);
registerIdlingResource();
}

Here is my sample code for that:
public class TestClass {
#Rule
public ActivityTestRule<T> activityRule = new ActivityTestRule<T>(type) {
#Override
protected void beforeActivityLaunched() {
//TODO inject mocks, setup stubs etc..
}
};
}
#Before
public void before() {
activityRule.getActivity();
}
#Test
public void myTest() {
//...
}
}

Is this code complete? I can't see you creating the dagger graph.
Anyway, what I do in my code, is to have a Static class called Injector that creates the graph for me, and also can inject elements into objects. So, in my Application Class I call it to create the graph, and all other activities just use the existent graph.
Then, in a test, you could create a fake test application class that initialize the graph in a different way, or simply recreate the graph calling the Injector methods, before the activity is created. I'm not familiar with ActivityTestRule, so I can't help much with the life cycle of this test.
But just make sure you create a new graph before the activity is created, and let the activity just use the existent graph.
How the activity access the graph? Well, I don't really love it, but we are used to access the application class (with explicit cast) and ask it to inject the dependencies for us. This is the way Dagger examples do it also.

android passing data from class to activity

I have been looking for a long time for a simple way to pass data (string type) from class to activity.
I found some tutorials about passing data from activity to class but is it possible to do the opposite, passing data from class to activity ?

if you import the class in your activity (which is also a class by the way) you can easily access the classes attributes.
example: MyClass.java
package edu.user.yourappname;
public class MyClass {
public string infoToPass = "whatever";
}
MyActivity.java
package edu.user.yourappname;
import edu.user.yourappname.MyClass
public class MyActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_my);
String myString = MyClass.infoToPass;
}
}
i have no IDE to type this in atm it might contain some errors :S but i hope you get the idea.
if you need more specific help you have to provide a code sample.
also, what do you want to achieve exactly? maybie there's a different approach.
cheers!

Create Interface and implement that in your activity. Pass the activity instance in your class and and call that instance with interface method whenever you like.

To be more clear, create an interface and use it as following:
public interface SomeInterface{
public void passValue(String value);
}
public SomeActivity extends Activity implements SomeInterface{
// place any code you want in your activity, onCreate, onResume, etc.
private void someMethod(){
// Wherever in your activity, initialize your class with your activity.
SomeClass someClass = new SomeClass(this);
someClass.someMethod();
}
public void passValue(String value){
// do whatever you want with your value
}
}
public class SomeClass{
private SomeInterface someInterfaceInstance;
public SomeClass(SomeInterface someInterfaceInstance){
this.someInterfaceInstance = someInterfaceInstance;
}
public void someMethod(){
// Some code...
someInterfaceInstance.passValue("Hello World!");
// Some more code...
}
}

Here is a easy way of doing it -
By defining static variables
In your class, make the String whose value you want to pass public static like this -
public static String pass;
And then in you activity, you can directly access it since it's a public variable like this -
String receive = className.pass;

How to Access Android Custom Application Object in simple Java Class which Also has ApplicationContext object?

I have created a custom application class like this:
class A extends android.app.Application{
public String abc = "xyz";
}
And I have a simple java class
class B {
private appContext;
// This constructor is called from activity.
B(Context ctx){
this.appContext = ctx;
}
private void foo(){
// want to access Class A's abc String vairable Here...HOW TO DO THAT?????
}
}
How to access Class A's abc String vairable in foo method.

You can get the Application class with getApplicationContext from Context with the good casting
((A) this.ctx.getApplicationContext()).abc;

The Application class in Android is a singleton and therefore so is your derived class. Android will create just one instance of your class A when it starts your application. Just change
class A extends android.app.Application {
public String abc = "xyz";
}
to
class A extends android.app.Application {
public static String abc = "xyz";
}
and you can reference it from anywhere like this:
String foo = A.abc;

Instead of passing a Context, try passing an instance of the Application class instead.
Something like:
class B {
private Application app;
// This constructor is called from activity.
B(Application ctx){
this.app = ctx;
}
private void foo(){
app.abc; //Do what you want
}
}
And call B like:
B b = new B(getApplication());
Make sure that this is in onCreate() or later.

Looks like you are already passing the application context as a parameter and initializing it in the constructor. So all you have to now is to use the context variable to access abc of A like the following way: ((A) this.appContext).abc;