Clarify LoggingApplicationListener Javadoc

spring-boot/src/main/java/org/springframework/boot/logging/LoggingApplicationListener.java

@@ -50,6 +50,12 @@ import org.springframework.util.StringUtils;
  * logging system, otherwise a default configuration is used. Regardless, logging levels
  * will be customized if the environment contains {@code logging.level.*} entries.
  * <p>
+ * Debug and trace logging for Spring, Tomcat, Jetty and Hibernate will be enabled when
+ * the environment contains {@code debug} or {@code trace} properties (i.e. if you start
+ * your application using {@literal java -jar myapp.jar [--debug | --trace]}). If you
+ * prefer to ignore these properties you can set {@link #setParseArgs(boolean) parseArgs}
+ * to {@code false}.
+ * <p>
  * By default, log output is only written to the console. If a log file is required the
  * {@code logging.path} and {@code logging.file} properties can be used.
  * <p>