/**
* Returns a new instance of {@code MessageDigest} that utilizes the specified algorithm.
*
* @param algorithm the name of the algorithm to use
* @return a new instance of {@code MessageDigest} that utilizes the specified algorithm
* @throws NoSuchAlgorithmException if the specified algorithm is not available
* @throws NullPointerException if {@code algorithm} is {@code null}
*/
public static MessageDigest getInstance(String algorithm) throws NoSuchAlgorithmException {
if (algorithm == null) {
throw new NullPointerException();
}
MessageDigest result;
synchronized (engine) {
engine.getInstance(algorithm, null);
if (engine.spi instanceof MessageDigest) {
result = (MessageDigest) engine.spi;
result.algorithm = algorithm;
result.provider = engine.provider;
return result;
}
return new MessageDigestImpl((MessageDigestSpi) engine.spi, engine.provider, algorithm);
}
}
