34 $ mvn test [INFO] --- maven-surefire-plugin:2.22.2:test (default-test) @ demo --- … [ERROR] Tests run: 1, Failures: 1, Errors: 0, Skipped: 0, Time elapsed: 0.532 s <<< FAILURE! - in com.kawakawaryuryu.boot15.demo.service.SampleServiceTest [ERROR] testSampleString(com.kawakawaryuryu.boot15.demo.service.SampleServiceTest) Time elapsed: 0.016 s <<< FAILURE! org.mockito.exceptions.verification.junit.ArgumentsAreDifferent: Argument(s) are different! Wanted: dependencyService.callString(<any string>); -> at com.kawakawaryuryu.boot15.demo.service.SampleServiceTest.testSampleString(SampleServiceTest.java:45) Actual invocation has different arguments: dependencyService.callString(null); -> at com.kawakawaryuryu.boot15.demo.service.SampleService.sampleString(SampleService.java:26) at com.kawakawaryuryu.boot15.demo.service.SampleServiceTest.testSampleString(SampleServiceTest.java:45)