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package sun.security.jca;

import java.lang.ref.*;

import java.security.*;

Collection of static utility methods used by the security framework.
Author:
 Andreas Sterbenz
Since:
  1.5/**
 * Collection of static utility methods used by the security framework.
 *
 * @author  Andreas Sterbenz
 * @since   1.5
 */
public final class JCAUtil {

    private JCAUtil() {
        // no instantiation
    }

    // size of the temporary arrays we use. Should fit into the CPU's 1st
    // level cache and could be adjusted based on the platform
    private static final int ARRAY_SIZE = 4096;

    
Get the size of a temporary buffer array to use in order to be
cache efficient. totalSize indicates the total amount of data to
be buffered. Used by the engineUpdate(ByteBuffer) methods.
/**
     * Get the size of a temporary buffer array to use in order to be
     * cache efficient. totalSize indicates the total amount of data to
     * be buffered. Used by the engineUpdate(ByteBuffer) methods.
     */
    public static int getTempArraySize(int totalSize) {
        return Math.min(ARRAY_SIZE, totalSize);
    }

    // cached SecureRandom instance
    private static class CachedSecureRandomHolder {
        public static SecureRandom instance = new SecureRandom();
    }

    
Get a SecureRandom instance. This method should be used by JDK
internal code in favor of calling "new SecureRandom()". That needs to
iterate through the provider table to find the default SecureRandom
implementation, which is fairly inefficient.
/**
     * Get a SecureRandom instance. This method should be used by JDK
     * internal code in favor of calling "new SecureRandom()". That needs to
     * iterate through the provider table to find the default SecureRandom
     * implementation, which is fairly inefficient.
     */
    public static SecureRandom getSecureRandom() {
        return CachedSecureRandomHolder.instance;
    }

}