org.mockito.exceptions.base.MockitoException: 
Cannot mock/spy class com.app.network.entity.Movies
Mockito cannot mock/spy because :
 - final class
How do i test this? Please assist
          
I did that but i still get the error. Not sure what else might be missing.
On Fri, Sep 7, 2018 at 8:04 AM Zak Taccardi ***@***.***> wrote:
 Use mock-maker-inline
 <https://github.com/mockito/mockito/wiki/What%27s-new-in-Mockito-2#mock-the-unmockable-opt-in-mocking-of-final-classesmethods>
 to mock final classes
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 <#285 (comment)>,
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I started seeing this when upgrading to mockito-kotlin2.  I've got mock-maker-inline set up (and was working fine with mockito-kotlin 1.5.0), but after upgrading to v2 I'm seeing:
Caused by: org.mockito.exceptions.base.MockitoException:
Mockito cannot mock this class: class org.jitsi.jibri.util.OsDetector.
Can not mock final classes with the following settings :
 - explicit serialization (e.g. withSettings().serializable())
 - extra interfaces (e.g. withSettings().extraInterfaces(...))
The class that causes it is final, but has no special settings that I know of:
enum class OsType {
    LINUX,
    UNSUPPORTED
class OsDetector {
    fun getOsType(): OsType {
        return when (System.getProperty("os.name")) {
            "Mac OS X" -> OsType.MAC
            "Linux" -> OsType.LINUX
            else -> OsType.UNSUPPORTED
I started seeing this when upgrading to mockito-kotlin2. I've got mock-maker-inline set up (and was working fine with mockito-kotlin 1.5.0), but after upgrading to v2 I'm seeing:
Caused by: org.mockito.exceptions.base.MockitoException:
Mockito cannot mock this class: class org.jitsi.jibri.util.OsDetector.
Can not mock final classes with the following settings :
 - explicit serialization (e.g. withSettings().serializable())
 - extra interfaces (e.g. withSettings().extraInterfaces(...))
The class that causes it is final, but has no special settings that I know of:
enum class OsType {
    LINUX,
    UNSUPPORTED
class OsDetector {
    fun getOsType(): OsType {
        return when (System.getProperty("os.name")) {
            "Mac OS X" -> OsType.MAC
            "Linux" -> OsType.LINUX
            else -> OsType.UNSUPPORTED
try to add
<dependency>
    <groupId>net.bytebuddy</groupId>
    <artifactId>byte-buddy</artifactId>
    <scope>test</scope>
</dependency>
to the dependencies
I started seeing this when upgrading to mockito-kotlin2. I've got mock-maker-inline set up (and was working fine with mockito-kotlin 1.5.0), but after upgrading to v2 I'm seeing:
Caused by: org.mockito.exceptions.base.MockitoException:
Mockito cannot mock this class: class org.jitsi.jibri.util.OsDetector.
Can not mock final classes with the following settings :
 - explicit serialization (e.g. withSettings().serializable())
 - extra interfaces (e.g. withSettings().extraInterfaces(...))
The class that causes it is final, but has no special settings that I know of:
enum class OsType {
    LINUX,
    UNSUPPORTED
class OsDetector {
    fun getOsType(): OsType {
        return when (System.getProperty("os.name")) {
            "Mac OS X" -> OsType.MAC
            "Linux" -> OsType.LINUX
            else -> OsType.UNSUPPORTED
try to add
<dependency>
    <groupId>net.bytebuddy</groupId>
    <artifactId>byte-buddy</artifactId>
    <scope>test</scope>
</dependency>
to the dependencies
I have the same error message when mocking JWTVerifier class (Java, not Kotlin), but adding the bytebuddy dependency doesn't solve the issue for me. This seems like a limitation of Mockito (Section 39: https://www.javadoc.io/doc/org.mockito/mockito-core/2.2.7/org/mockito/Mockito.html#Mocking_Final). Is there any way to bypass it?
Mockito cannot mock this class: class com.auth0.jwt.JWTVerifier.
Can not mock final classes with the following settings :
 - explicit serialization (e.g. withSettings().serializable())
 - extra interfaces (e.g. withSettings().extraInterfaces(...))
public final class JWTVerifier implements com.auth0.jwt.interfaces.JWTVerifier {
    private final Algorithm algorithm;
    final Map<String, Object> claims;
    private final Clock clock;
    private final JWTParser parser;
    JWTVerifier(Algorithm algorithm, Map<String, Object> claims, Clock clock) {
        this.algorithm = algorithm;
        this.claims = Collections.unmodifiableMap(claims);
        this.clock = clock;
        this.parser = new JWTParser();
    static Verification init(Algorithm algorithm) throws IllegalArgumentException {
        return new JWTVerifier.BaseVerification(algorithm);
    public DecodedJWT verify(String token) throws JWTVerificationException {
        DecodedJWT jwt = new JWTDecoder(this.parser, token);
        return this.verify((DecodedJWT)jwt);
    public DecodedJWT verify(DecodedJWT jwt) throws JWTVerificationException {
        this.verifyAlgorithm(jwt, this.algorithm);
        this.algorithm.verify(jwt);
        this.verifyClaims(jwt, this.claims);
        return jwt;
          
@meganzhao10 A lot has changed since mockito-kotlin 1.5.0. This looks like a problem related to the creation of your mock.
Could you please share the test.
          
@bohsen This is the test file. I'm able to run the tests successfully in IntelliJ. But mvn test failed with the message that I think it's part of Mockito limitations:
class ControllerTest {
    private Controller controller;
    @Mock
    private JWTVerifier verifier;
    @BeforeEach
    void setUp() {
        initMocks(this);
        controller = new Controller(verifier);
    @Test
    void testFunc1() {
I also included the pom.xml dependencies if that's helpful
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
            <version>2.9.10.3</version>
        </dependency>
        <dependency>
            <groupId>io.lettuce</groupId>
            <artifactId>lettuce-core</artifactId>
            <version>5.2.1.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>com.auth0</groupId>
            <artifactId>java-jwt</artifactId>
            <version>3.9.0</version>
        </dependency>
        <dependency>
            <groupId>org.junit.jupiter</groupId>
            <artifactId>junit-jupiter-engine</artifactId>
            <version>${junit-jupiter.version}</version>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>com.github.stefanbirkner</groupId>
            <artifactId>system-rules</artifactId>
            <version>1.17.2</version>
        </dependency>
        <dependency>
            <groupId>org.mockito</groupId>
            <artifactId>mockito-core</artifactId>
            <version>2.24.0</version>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.mockito</groupId>
            <artifactId>mockito-junit-jupiter</artifactId>
            <version>${mockito.version}</version>
            <scope>test</scope>
        </dependency>
    </dependencies>