java 用Java在一定范围内均匀生成安全随机数
声明:本页面是StackOverFlow热门问题的中英对照翻译,遵循CC BY-SA 4.0协议,如果您需要使用它,必须同样遵循CC BY-SA许可,注明原文地址和作者信息,同时你必须将它归于原作者(不是我):StackOverFlow
原文地址: http://stackoverflow.com/questions/28742702/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
Generate secure random number uniformly over a range in Java
提问by anoopelias
How do I generate a secure uniformrandom number within a range? The range could be between 0 to 100. (The upper bound is not a power of 2).
如何在一个范围内生成一个安全的统一随机数?范围可以在 0 到 100 之间。(上限不是 2 的幂)。
java.security.SecureRandom
seems to provide the range 0..2^n
.
java.security.SecureRandom
似乎提供了 range 0..2^n
。
回答by Peter Lawrey
You can do
你可以做
Random rand = new SecureRandom()
// 0 to 100 inclusive.
int number = rand.nextInt(101);
or
或者
// 0 inclusive to 100 exclusive.
int number = rand.nextInt(100);
Note: this is more efficient than say (int) (rand.nexDouble() * 100)
as nextDouble() needs to create at least 53-bits of randomness whereas nextInt(100) creates less than 7 bits.
注意:这比(int) (rand.nexDouble() * 100)
因为 nextDouble() 需要创建至少 53 位随机性而 nextInt(100) 创建少于 7 位的说法更有效。
回答by Snehal Patel
Try below code snap
尝试下面的代码快照
SecureRandom random = new SecureRandom();
int max=50;
int min =1;
System.out.println(random.nextInt(max-min+1)+min);