4.0.0 org.springframework.boot spring-boot-starter-parent 2.3.4.RELEASE io.spring.cloud.stream.sample image-thumbnail-processor 0.0.1-SNAPSHOT image-thumbnail-processor Thumbnail processor 8 org.junit.jupiter junit-jupiter 5.6.2 test org.assertj assertj-core 3.16.1 org.springframework spring-core 5.2.8.RELEASE test