You might've forgot to add a dependency or it's written wrong. Also, you might be using incompatible versions of Java and Hibernate. More on this here: https://goo.gl/SjSlRA
If you're using Hibernate, this indicates you're missing FasterXML Classmate dependency, which you can add to your dependencies. To add it, the groupId is com.fasterxml and artifactId is Classmate.
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