How Do You Mock A Void Return?

How do you mock a void in JUnit?

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 mock a void in EasyMock?

If we just want to mock void method and don’t want to perform any logic, we can simply use expectLastCall(). andVoid() right after calling void method on mocked object. You can checkout complete project and more EasyMock examples from our GitHub Repository.

How do you return a void test?

Therefore, testing of these methods consists of these three steps:Set the object being tested to the initial state before calling the parameterless method.Call the parameterless method.Check the return value or the side effects of the parameterless method.

How does EasyMock work?

EasyMock instantiates an object based on an interface or class. … The expect() method tells EasyMock to simulate a method with certain arguments. The andReturn() method defines the return value of this method for the specified method parameters. The times() method defines how often the Mock object will be called.

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.

How do you assert 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…

Can we write JUnit test cases for void methods?

Conclusion. In this example, we have learned that how we can JUnit Test Void Method. We have also learned that how to catch the exception if it is thrown by a void method. Actually testing mechanism is same for all methods, but void methods are special as we don’t have any returning value to be matched for testing.

What is replay EasyMock?

The replay method is used to pass the mock from recording (where you record the method you expect to be called) to replaying state (where you actually test).

How do you mock a private method?

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.

How do you call a real method on mocked object?

Use Mockito’s thenCallRealMethod() to Call a Real MethodThe Object to Be Mocked.Use Mockito to Mock an Object.Stubbing Mock Object with Mockito.Use Mockito thenCallRealMethod()Test Class Complete Example.