public static int findAvailableUdpPort() {
        return findAvailableUdpPort(PORT_RANGE_MIN);
    }
Find an available UDP port randomly selected from the range [{@value #PORT_RANGE_MIN}, {@value #PORT_RANGE_MAX}].

@return an available UDP port number
@throws IllegalStateException if no available port could be found
grpc-common-spring-boot/src/main/java/net/devh/boot/grpc/common/util/SocketUtils.java