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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

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 * particular file as subject to the "Classpath" exception as provided

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 * accompanied this code).

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package sun.security.provider;

/**

 * An interface of a source of entropy input.

 *

 * @since 9

 */

public interface EntropySource {

    /**

     * Returns a byte array containing entropy.

     * <p>

     * This maps to the {@code Get_entropy_input} function defined in

     * Section 9 of NIST SP 800-90Ar1.

     *

     * @param minEntropy minimum entropy required, in bytes

     * @param minLength minimum length of output, in bytes

     * @param maxLength maximum length of output, in bytes

     * @param pr whether prediction resistance is required

     * @return the byte array containing entropy

     */

    byte[] getEntropy(int minEntropy, int minLength, int maxLength, boolean pr);

}