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in Technique[技术] by (71.8m points)

How can I use random numbers in groovy?

I use this method:

def getRandomNumber(int num){
    Random random = new Random()
    return random.getRandomDigits(num)
}

when I call it I write println getRandomNumber(4)

but I have an error

No signature of method: java.util.Random.getRandomDigits() is applicable for argument types: (java.lang.Integer) values: [4]

Note: I use this method in another groovy class and it works properly without any error.

question from:https://stackoverflow.com/questions/4244149/how-can-i-use-random-numbers-in-groovy

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by (71.8m points)

There is no such method as java.util.Random.getRandomDigits.

To get a random number use nextInt:

return random.nextInt(10 ** num)

Also you should create the random object once when your application starts:

Random random = new Random()

You should not create a new random object every time you want a new random number. Doing this destroys the randomness.


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