Mockito cannot mock a static method

Question

I don't know what's wrong with my code, none of my static method can be mocked by Mockito...

I have checked for couple of hours, and it seems that I have nothing wrong in my code.

here is the dependency:

            <dependency>
                <groupId>org.mockito</groupId>
                <artifactId>mockito-core</artifactId>
                <version>3.12.4</version>
                <scope>test</scope>
            </dependency>
            <dependency>
                <groupId>org.mockito</groupId>
                <artifactId>mockito-inline</artifactId>
                <version>3.12.4</version>
                <scope>test</scope>
            </dependency>

here is the static method:

public class FakeTokenUtil {
    public static String getToken(){
        return "123123123123";
    }
}

here is the test class:

@RunWith(MockitoJUnitRunner.class)
public class TokenTest {
    @Test
    public void mockStatic() {
        MockedStatic<FakeTokenUtil> mock=Mockito.mockStatic(FakeTokenUtil.class);
        mock.when(FakeTokenUtil::getToken).thenReturn("666666");
        System.out.println(FakeTokenUtil.getToken());
    }
}

after running the test, I got this exception:

org.mockito.exceptions.base.MockitoException: 
The used MockMaker SubclassByteBuddyMockMaker does not support the creation of static mocks

Mockito's inline mock maker supports static mocks based on the Instrumentation API.
You can simply enable this mock mode, by placing the 'mockito-inline' artifact where you are currently using 'mockito-core'.
Note that Mockito's inline mock maker is not supported on Android.

    at com.test.myapp.service.TokenTest.mockStatic(TokenTest.java:13)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:59)
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
    at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:56)
    at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
    at org.mockito.internal.runners.DefaultInternalRunner$1$1.evaluate(DefaultInternalRunner.java:55)
    at org.junit.runners.ParentRunner$3.evaluate(ParentRunner.java:306)
    at org.junit.runners.BlockJUnit4ClassRunner$1.evaluate(BlockJUnit4ClassRunner.java:100)
    at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:366)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:103)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:63)
    at org.junit.runners.ParentRunner$4.run(ParentRunner.java:331)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:79)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:329)
    at org.junit.runners.ParentRunner.access$100(ParentRunner.java:66)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:293)
    at org.junit.runners.ParentRunner$3.evaluate(ParentRunner.java:306)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:413)
    at org.mockito.internal.runners.DefaultInternalRunner$1.run(DefaultInternalRunner.java:100)
    at org.mockito.internal.runners.DefaultInternalRunner.run(DefaultInternalRunner.java:107)
    at org.mockito.internal.runners.StrictRunner.run(StrictRunner.java:41)
    at org.mockito.junit.MockitoJUnitRunner.run(MockitoJUnitRunner.java:163)
    at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
    at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:68)
    at com.intellij.rt.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:33)
    at com.intellij.rt.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:230)
    at com.intellij.rt.junit.JUnitStarter.main(JUnitStarter.java:58)

Answer 1

From the doc:

Try to add a file src/test/resources/mockito-extensions/org.mockito.plugins.MockMaker with a single line

mock-maker-inline

This feature comes at a slight performance cost, though. I usually try to avoid this kind of mocking. Maybe you should reconsider your code, too. if it is a simple and predictable utility method, there is no need to mock it for a test. If it is rather a dependency to another component, then it should be an instance method.