Quick Answer: What Is The Difference Between DoReturn And ThenReturn?

Do you answer Mockito?

Answer is used when you need to do additional actions when a mocked method is invoked, e.g.

when you need to compute the return value based on the parameters of this method call.

Use doAnswer() when you want to stub a void method with generic Answer ..

What is the difference between spy and mock?

Mocks are used to create fully mock or dummy objects. It is mainly used in large test suites. Spies are used for creating partial or half mock objects. Like mock, spies are also used in large test suites.

What does when do in Mockito?

When the when method is invoked after the invocation of method() , it delegates to MockitoCore. when , which calls the stub() method of the same class. This method unpacks the ongoing stubbing from the shared MockingProgress instance that the mocked method() invocation wrote into, and returns it.

What is doAnswer Mockito?

Use doAnswer() when you want to stub a void method with generic Answer . Answer specifies an action that is executed and a return value that is returned when you interact with the mock.

Why would you use a spy in a test?

Spies are an easy way to check if a function was called or to provide a custom return value. We can use spies to test components that depend on a service and avoid actually calling the service’s methods to get a value.

How do you mock a void method?

Mockito provides following methods that can be used to mock void methods. doAnswer() : We can use this to perform some operations when a mocked object method is called that is returning void. doThrow() : We can use doThrow() when we want to stub a void method that throws exception.

How do you mock a void function?

How to mock void method in mockito?doNothing() : Completely ignore the calling of void method, this is default behavior.doAnswer() : Perform some run time or complex operations when void method is called.doThrow() : Throw exception when mocked void method is called.doCallRealMethod() : Do not mock and call real method.

How do you test a void method?

How to verify that void methods were called using MockitoThe class under test is never mocked.The dependencies of the class under test need to be mocked.By calling a method on a mock object we will mock that method call.In your test, first perform the action under test then call verify() not the other way around.More items…

Do nothing when a method is called Mockito?

doNothing: Is the easiest of the list, basically it tells Mockito to do nothing when a method in a mock object is called. Sometimes used in void return methods or method that does not have side effects, or are not related to the unit testing you are doing.

Can we mock private methods?

For Mockito, there is no direct support to mock private and static methods. In order to test private methods, you will need to refactor the code to change the access to protected (or package) and you will have to avoid static/final methods. … But, there are frameworks which support mocking for private and static methods.

Why do we need Mockito?

Mockito is a popular mock framework which can be used in conjunction with JUnit. Mockito allows you to create and configure mock objects. Using Mockito greatly simplifies the development of tests for classes with external dependencies.

Can we mock an interface?

The Mockito. mock() method allows us to create a mock object of a class or an interface. Then, we can use the mock to stub return values for its methods and verify if they were called. This method doesn’t need anything else to be done before it can be used.