How to mock methods of @InjectMocks class in java?

How to mock methods of @InjectMocks class in java?

To mock methods of a class annotated with @InjectMocks in Java, you can use the Mockito framework along with @Mock annotations for the dependencies. Here's how you can do it:

Assuming you have a class that you want to test, and it has some dependencies:

import org.springframework.stereotype.Service; @Service public class MyService { private MyDependency myDependency; public MyService(MyDependency myDependency) { this.myDependency = myDependency; } public String doSomething() { // Call a method on the dependency return myDependency.doAnotherThing(); } }

Here's how you can write a test to mock the method of the @InjectMocks class MyService:

import org.junit.jupiter.api.BeforeEach; import org.junit.jupiter.api.Test; import org.mockito.InjectMocks; import org.mockito.Mock; import org.mockito.MockitoAnnotations; import static org.junit.jupiter.api.Assertions.assertEquals; import static org.mockito.Mockito.when; public class MyServiceTest { @InjectMocks private MyService myService; @Mock private MyDependency myDependency; @BeforeEach public void setUp() { // Initialize mocks and inject them into the @InjectMocks instance MockitoAnnotations.initMocks(this); } @Test public void testDoSomething() { // Define the behavior of the mocked method when(myDependency.doAnotherThing()).thenReturn("Mocked result"); // Call the method being tested String result = myService.doSomething(); // Verify the result assertEquals("Mocked result", result); } }

In this example:

  1. We use the @InjectMocks annotation to inject an instance of MyService that we want to test.

  2. We use the @Mock annotation to create a mock instance of MyDependency, which is a dependency of MyService.

  3. In the setUp method annotated with @BeforeEach, we initialize the mocks and inject them into the @InjectMocks instance using MockitoAnnotations.initMocks(this).

  4. In the testDoSomething method, we define the behavior of the mocked method doAnotherThing using when(myDependency.doAnotherThing()).thenReturn("Mocked result").

  5. We then call the method being tested (doSomething in this case), and we can verify the result.

By using Mockito and properly annotating your test class and fields with @InjectMocks and @Mock, you can effectively mock methods of a class annotated with @InjectMocks for testing purposes.

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angular-http-interceptors python-mock pdb twisted jdbctemplate collocation iterator 3des set-intersection database-partitioning

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