How Do You Test A Void Method?

What is the difference between public void and private void?

The keywords ‘public’ and ‘void’ designate different things about a method; they are not related to the same concept.

There are other designations — private and protected — that mean other things; private, for instance, designates a method that can only be called from within the class in which it is declared..

Does void return anything?

The void functions are called void because they do not return anything. … From a void function, we cannot return any values, but we can return something other than values.

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.

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 test a method which does not return any value?

If a method is not returning anything through the “return” statement (void method), it may return data through its arguments. In this case, you can test the data returned in any argument. Else if a method is not returning any data through its arguments, it may change values of its instance variables.

What are the features of J unit?

Features of JUnitJUnit is an open source framework, which is used for writing and running tests.Provides annotations to identify test methods.Provides assertions for testing expected results.Provides test runners for running tests.JUnit tests allow you to write codes faster, which increases quality.More items…

How do you write a JUnit test case in Java?

Following are the most commonly used annotations and their usage in a basic unit test written in JUnit 4.@Test – Marks the method as a test method.@Before and @After sandwiches each test method in the class.@BeforeClass and @AfterClass sandwiches all of the test methods in a JUnit test class.More items…•

How do you check if a method returns void?

It is possible to test methods that don’t return anything ( void ), but you must test that method’s side effects….You’d test this method by:Creating an ArrayList arr ;Adding some things to it;Invoking arr. clear() ;Checking assertEquals(arr. size(),0) .

Can you unit test a void method?

You can do it by using ref keyword. First Create a void method with a ref parameter in your Class Library Solution. Out goal is to test this void method in unit test. Calling the methodRef in Test Class.

What are void methods?

The void Keyword This method is a void method, which does not return any value. Call to a void method must be a statement i.e. methodRankPoints(255.7);. It is a Java statement which ends with a semicolon as shown in the following example.

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 a void return type?

A Guide to “Void” in Computer Programming In computer programming, when void is used as a function return type, it indicates that the function does not return a value. … When used in a function’s parameter list, void indicates that the function takes no parameters.