This extends 6 JUnit & JMockit interview questions & answers on Java Unit testing – Part 1. It is very essential to understand how these 3 annotations work in JMockit to write unit tests quickly & effectively.
Q1 What is the difference between @Injectable and @Mocked in JMockit?
…
JUnit with Mockito tutorial step by step. Mockito is a popular mocking framework used along with JUnit. JMockit is more popular than Mockito.
Step 1: Create a simple maven project say “code-quality”
|
1 |
mvn -B archetype:generate -DgroupId=com.mytutorial -DartifactId=code-quality |
Step 2: Import into eclipse.
…
Firstly, you need the pom.xml entry to bring in the Mockito library.
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 |
... <dependency> <groupId>org.junit.jupiter</groupId> <artifactId>junit-jupiter-engine</artifactId> <version>5.9.2</version> <scope>test</scope> </dependency> <dependency> <groupId>org.junit.platform</groupId> <artifactId>junit-platform-runner</artifactId> <version>1.9.2</version> <scope>test</scope> </dependency> <dependency> <groupId>org.mockito</groupId> <artifactId>mockito-core</artifactId> <version>3.10.0</version> <scope>test</scope> </dependency> ... |
@InjectMocks
Firstly, annotate the Test class with @RunWith(MockitoJUnitRunner.class) as shown below. The @InjectMocks annotation creates an instance of the class and injects the mocks that are created with the @Mock (or @Spy) annotations into this instance.
…
This extends 01: JMockit interview Q&As on @Injectable Vs @Mocked Vs @Tested. The purpose of mocking objects is to return an expected value to test the logic of the class under test. This can be achieved with JMockit Expectations.
An expectation represents a set of invocations to a specific mocked method/constructor that is relevant for a given test.
…
A spy in mockito is a partial mock where part of the object will be mocked and part will use real method invocations. You can create a Spy a number of different ways. Consider using mocks instead of spies wherever possible as having to use a Spy could indicate violating...
Step 1: Create a simple Maven project from a command-line. Just press enter for all the prompts.
|
1 |
mvn archetype:generate -DgroupId=com.mytutorial -DartifactId=simple-mocking-test |
Step 2: Import the above “simple-mocking-test” in the file system into eclipse. File –> Import –> “Existing Maven Projects” and then select the “simple-mocking-test”
…
This extends 02: JMockit interview Q&As & examples on Expectations & Verifications. We have already discussed that a non-final instance field annotated as @Tested in the test class will be considered for automatic instantiation and injection, just before the execution of a test method. … Read more ›...
Unlike a @Spy where you are spying on a real object, when you mock, you are creating a complete mock or fake object. Q: What are the different ways to mock an object? A: There are 3 ways to mock a dependent class that is sed by the class under...
This extends Part 1: Unit testing with JUnit, Mockito & Spring by mocking the DAO layer with the Mockito framework. Step 1: Service and DAO layer interfaces and implementations Service Layer
|
1 2 3 4 5 |
package com.mytutorial; public interface SimpleService { abstract String processUser(int id); } |
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 |
package com.mytutorial; import javax.inject.Inject; import javax.inject.Named; @Named public class SimpleServiceImpl implements SimpleService { @Inject SimpleDao dao; public String processUser(int id) { String name = dao.getNameById(id); return "Hello " + name; } } |
DAO Layer This layer will be mocked by Mockito in the next step. … Read more ›...
This extends 01: JMockit interview Q&As on @Injectable Vs @Mocked Vs @Tested. The purpose of mocking objects is to return an expected value to test the logic of the class under test. This can be achieved with JMockit Expectations. Q1. … Read more ›...
Let’s look at step by step to understand how to mock private & static methods with PowerMock & JUnit. pom.xml Step 1: The pom.xml file should have Mockito & Powermock libraries.
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 |
... <dependency> <groupId>org.junit.jupiter</groupId> <artifactId>junit-jupiter-engine</artifactId> <version>5.9.2</version> <scope>test</scope> </dependency> <dependency> <groupId>org.junit.platform</groupId> <artifactId>junit-platform-runner</artifactId> <version>1.9.2</version> <scope>test</scope> </dependency> <dependency> <groupId>org.mockito</groupId> <artifactId>mockito-core</artifactId> <version>3.10.0</version> <scope>test</scope> </dependency> <dependency> <groupId>org.powermock</groupId> <artifactId>powermock-module-junit4</artifactId> <version>2.0.2</version> <scope>test</scope> </dependency> <!-- PowerMock Mockito2 API --> <dependency> <groupId>org.powermock</groupId> <artifactId>powermock-api-mockito2</artifactId> <version>2.0.2</version> <scope>test</scope> </dependency> ... |
Config & Service classes to test Step 2: The implementation classes that need to be tested. … Read...
This extends Part 2: Mockito to fully mock the DAO layer by modifying the service layer to demonstrate partial mocking with “Mockito.spy”. In the “SimpleServiceImpl” we are interested in only testing the method “processUser(int id)” and want to mock the method “getUserById(int id)” by always returning “Sam”. So, … Read...
This extends Mockit interview Q&As & examples on @Injectable Vs @Mocked Vs @Capturing Vs @Tested. Why partial mocking? All methods that can be called on a mocked instance get mocked. This is appropriate for most tests, but in some situations we might need to select only certain methods to be...
