nanoseconds and random numbers

Random is pseudo-random, that is, when the seed is determined, the sequence of stochastic numbers is determined.
So the seed is the key of the random number, if the constructor does not pass the seed, the secret exists in the value of nanotime, guess this value will be more difficult, 1 milliseconds =1k subtle =1m nanosecond =1b picosecond; If you can accurately predict the millisecond, the calculation of 1 million sequences must have a right, and if you use the specified seed , all the secrets are in that seed. The nanosecond number is a long, which can support a continuous count of 296 years.
It is foolish to specify a seed for the random.

Java has used this mentally retarded algorithm for portability, but if you ask for a high-securerandom, see the API documentation.

nanoseconds and random numbers