20 lines
522 B
Kotlin
20 lines
522 B
Kotlin
package org.session.libsignal.crypto
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import java.security.SecureRandom
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/**
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* Uses `SecureRandom` to pick an element from this collection.
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*/
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fun <T> Collection<T>.getRandomElementOrNull(): T? {
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if (isEmpty()) return null
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val index = SecureRandom().nextInt(size) // SecureRandom() should be cryptographically secure
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return elementAtOrNull(index)
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}
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/**
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* Uses `SecureRandom` to pick an element from this collection.
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*/
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fun <T> Collection<T>.getRandomElement(): T {
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return getRandomElementOrNull()!!
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}
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