It's not the same without you

Join the community to find out what other Atlassian users are discussing, debating and creating.

Atlassian Community Hero Image Collage

How can i make use of mockito to resolve a null pointer exception in my test junit method which are concerned with license of a plugin?

I mock ThirdPartyPluginLicenseStorageManager and PluginLicense.class using mockito in a junit test.

But while calling the internal methods of them it throws null pointer exception.

How can i overcome them as i dont see a way of setting the values in the mock confluence license objects

 

Few lines in my macro stub

@Mock
private ThirdPartyPluginLicenseStorageManager licenseManager;

@Before
public void setUp() throws Exception {
   super.setUp();
   exampleMacro = new Macro(licenseManager);
   PluginLicense pluginLicense = Mockito.mock(PluginLicense.class);
}

@Test
public void test() throws Exception {

   when(pluginLicense.getError().isDefined()).thenReturn(Boolean.FALSE); // Null pointer Exception
   when(licenseManager.getLicense().isDefined()).thenReturn(Boolean.TRUE); // Null pointer Exception

}

 

 

Few lines in my macro code which are throwing null pointer exception

private final ThirdPartyPluginLicenseStorageManager licenseManager;

public Macro(ThirdPartyPluginLicenseStorageManager licenseManager){
        this.licenseManager = licenseManager;
}

PluginLicense pluginLicense = licenseManager.getLicense().get();
if(licenseManager.getLicense().isDefined()) {
	if(pluginLicense.getError().isDefined()) {
	
	}
}

 

 

2 answers

In the mock code you showed, in the setup method you mock a pluginLicense object. In test method you use another object.

Move this

PluginLicense pluginLicense = Mockito.mock(PluginLicense.class);

in the global declaration just below your licenseManager and delete any other pluginLicense that you have declared somewhere else.

Did that @Mock private PluginLicense pluginLicense; Same null pointer exception error.

PluginLicense pluginLicense = licenseManager.getLicense().get(); is this mocked?

i am new to mockito Can you just give me an example of how to mock this statement as there is no setter method like licenseManager.setLicense() to it. How to mock this?

Generally the idea is like... when(mockedObject.method()).thenReturn(something) right? In your occassion, licenseManager.getLicense() returns an Option<PluginLicense> so the mock should be:

when(licenseManager.getLicense()).thenReturn(Option.option(pluginLicense));

This is untested though :smile:

 

In mockito you dont do setters. Lets say you have an interface method that with parameter string X returns object T and another method that with object T, returns string X.

the you would

Mockito.when(myInterface.myMethod(anyString())).thenReturn(T); //Notice the anyString() in this case i dont care what the param is.

the second case would be

Mockito.when(myInterface.myOtherMethod(T)).thenReturn(X);

To mock correctly i suggest you a) read documentation ofc and b) have the documentation of the method signatures on hand.

This was helpful but I had to use PowerMock instead of Mockito because the `isDefined` method is final :(

 

I ended up making my own Mock version of PluginLicenseManager with a method like this:

 

@Override
public Option<PluginLicense> getLicense() {
Option<PluginLicense> option = PowerMockito.mock(Option.class);

PluginLicense pluginLicense = PowerMockito.mock(PluginLicense.class);
Option<PluginLicense> optionError = PowerMockito.mock(Option.class);
PowerMockito.doReturn(error).when(optionError).isDefined();
PowerMockito.doReturn(optionError).when(pluginLicense).getError();

PowerMockito.doReturn(licensed).when(option).isDefined();
PowerMockito.doReturn(pluginLicense).when(option).get();

return option;
}

 

error and license being simple booleans defined as part of the class.

 

Also had to make sure my test runner was annotated:

@RunWith(PowerMockRunner.class)
@PrepareForTest(Option.class)

 

Still get some strange warnings from the depths of PowerMock but it works...

 

WARNING: Illegal reflective access by org.powermock.reflect.internal.WhiteboxImpl (file:/home/geoff/.m2/repository/org/powermock/powermock-reflect/2.0.2/powermock-reflect-2.0.2.jar) to method java.lang.Object.clone()
WARNING: Please consider reporting this to the maintainers of org.powermock.reflect.internal.WhiteboxImpl
WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations
WARNING: All illegal access operations will be denied in a future release

 HTH

Suggest an answer

Log in or Sign up to answer
TAGS
Community showcase
Posted in Confluence

What project did you transition or start on Confluence with the shift to remote work?

It’s been great to hear from fellow users over the last few weeks about the best tips and fun moments you’ve had working on Confluence since the transition to working remote. I’d love to keep the c...

32 views 2 4
Join discussion

Community Events

Connect with like-minded Atlassian users at free events near you!

Find an event

Connect with like-minded Atlassian users at free events near you!

Unfortunately there are no Community Events near you at the moment.

Host an event

You're one step closer to meeting fellow Atlassian users at your local event. Learn more about Community Events

Events near you