3-3-logger: AirportController.java

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

public class AirportController {
    private final Bucket bucket;
  	private final Log logger = LogFactory.getLog(getClass());
  	
  	public List<String> airportNamesStartingWith(@RequestParam String prefix) {
  	  N1qlQuery query = ...;
  	  logger.trace(query.statement());
  	}
}

logback.xml

<?xml version="1.0" encoding="UTF-8"?>
<configuration>
    <include resource="org/springframework/boot/logging/logback/base.xml"/>
    <logger name="com.couchbase.workshop" level="TRACE"/>
</configuration>