To anyone out there experiencing this error: Check your pom.xml to see if it contains this dependency:
<dependency>
<groupId>org.apache.cxf</groupId>
<artifactId>cxf-bundle-jaxrs</artifactId>
<version>2.7.0</version>
</dependency>
This is the jar for jersey I guess, kill it with fire if you want to use resteasy.