Error building json-producer example

https://docs.couchbase.com/kafka-connector/current/quickstart.html#send-test-messages states
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Now that the Couchbase Sink Connector is running, let’s give it some messages to import:

git clone https://github.com/couchbase/kafka-connect-couchbase.git
cd kafka-connect-couchbase/examples/json-producer
mvn compile exec:java
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However
mvn compile exec:java
creates these errors:
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[ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.1:compile (default-compile) on project json-producer-example: Compilation failure: Compilation failure:
[ERROR] Source option 5 is no longer supported. Use 6 or later.
[ERROR] Target option 1.5 is no longer supported. Use 1.6 or later.
[ERROR] -> [Help 1]
[ERROR]
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR]
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/MojoFailureException
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