The Java SDK for Couchbase has multiple logging frameworks available, including the simple default logger, SunLogger (based on java.util.logging), Log4J, and SLF4J. The SDK supports logging to STDERR from INFO level up, as well as to external loggers like Log4J and the SunLogger. To switch between these logging mechanisms, users can set a system property or use a Java command-line argument. Each logger has its own mapping of log levels, so some level mappings may not be available for all loggers. The SDK will support SLF4J in future releases, allowing users to plug in their preferred logging framework.