public static SortedSet<Integer> findAvailableUdpPorts(int numRequested) {
        return findAvailableUdpPorts(numRequested, PORT_RANGE_MIN, PORT_RANGE_MAX);
    }
Find the requested number of available UDP ports, each randomly selected from the range
[{@value #PORT_RANGE_MIN}, {@value #PORT_RANGE_MAX}].

@param numRequested the number of available ports to find
@return a sorted set of available UDP port numbers
@throws IllegalStateException if the requested number of available ports could not be found
grpc-common-spring-boot/src/main/java/net/devh/boot/grpc/common/util/SocketUtils.java