doclint reports:
open/src/jdk.management.jfr/share/classes/jdk/management/jfr/FlightRecorderMXBean.java:213: warning: @return has already been specified
     * @return a unique ID that can be used for reading recording data.
       ^
1 warning

The source shows:
     * @return a snapshot of all available recording data, not {@code null}
     *
     * @throws java.lang.SecurityException if a security manager exists and the
     * caller does not have {@code ManagementPermission("control")}
     *
     * @return a unique ID that can be used for reading recording data.