Could not initialize plugin: interface org.mockito.plugins.MockMaker

Question

I\'m getting following exception once tests is started:

    Testcase: treeCtorArgumentTest(com.xythos.client.drive.cachedtree.CachedTreeTest):  Caused an ERR         


        

Answer 1

I had Byte Buddy on classpath (is transitive dep of Mockito 2.8.9) and still got the exception. Reason for me was that I ran the Unit tests with JRE instead of JDK. Switching to JDK worked for me.

Answer 2

I had the same exception when switch to Java 10 and Spring Boot 2. This dependency combination worked for me:

    <dependency>
        <groupId>org.mockito</groupId>
        <artifactId>mockito-all</artifactId>
        <version>2.0.2-beta</version>
        <scope>test</scope>
    </dependency>
    <dependency>
        <groupId>net.bytebuddy</groupId>
        <artifactId>byte-buddy</artifactId>
        <version>1.8.16</version>
    </dependency>
    <dependency>
        <groupId>net.bytebuddy</groupId>
        <artifactId>byte-buddy-agent</artifactId>
        <version>1.8.16</version>
        <scope>test</scope>
    </dependency>

Answer 3

Adding a bnd aspect to this

Adding on to Paskas' answer, you also have to include the dependencies in the cnf maven repository, if you're using one (like my cnf/central.mvn).

org.mockito:mockito-core:2.21.0
net.bytebuddy:byte-buddy:1.8.15
net.bytebuddy:byte-buddy-agent:1.8.15
org.objenesis:objenesis:2.6

and for convenient referencing, you can include a bnd variable in your cnf/build.bnd

mockito: org.mockito:mockito-core; version=2.21.0,\
         net.bytebuddy:byte-buddy; version=1.8.15,\
         net.bytebuddy:byte-buddy-agent; version=1.8.15,\
         org.objenesis:objenesis; version=2.6

and in your project's bnd file

-testpath:\
    ${mockito}

Answer 4

If you are using powermock ensure that your dependencies point to:

org.powermock:powermock-api-mockito2

instead of

org.powermock:powermock-api-mockito

Answer 5

I encountered this issue and solved it by bumping my version of org.mockito.mockito-core to the latest release. I had been using an older release for quite some time.

Answer 6

My dependency for mockito was under androidTestImplementation and not under testImplementation.

I got the same error when I tried to use mockito with my unit tests. All I had to do was add the dependency.