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java.util
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java.lang.Object

java.util.Random
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Serializable
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SecureRandom
public class Random
extends Object
implements Serializable
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Math.random()
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Random
()
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Random
(long seed)
          Ê¹Óõ¥¸ö long
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public Random(long seed) { setSeed(seed); }
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protected  int
next
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nextBoolean
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nextBytes
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nextDouble
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nextFloat
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