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Pseudorandom number generators (PRNGs) use deterministic mathematical algorithms to produce a sequence of numbers with good statistical properties, but the numbers produced are not genuinely random. PRNGs usually start with an arithmetic seed value. The algorithm uses this seed in order to generate an output value and a new seed as well, which is used to generate the next value, and so on.
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If you use the same seed value, you will always get the same sequence of numbers; thus as a result they will not be "random".
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This compliant solution uses the java.security.SecureRandom class in order to produce high quality random numbers.
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