<project>
  ...
  <dependencies>
    <dependency>
      <groupId>org.elasticsearch</groupId>
      <artifactId>elasticsearch</artifactId>
      <version>6.2.4</version>
      <scope>compile</scope>
      <exclusions>
        <exclusion>  <!-- declare the exclusion here -->
          <groupId>com.fasterxml.jackson.core</groupId>
          <artifactId>jackson-core</artifactId>
        </exclusion>
      </exclusions>
    </dependency>
  </dependencies>
</project>