@Override
    public Hash hashPassword(Object plaintext) {
        ByteSource plaintextBytes = createByteSource(plaintext);
        if (plaintextBytes == null || plaintextBytes.isEmpty()) {
            return null;
        }
        HashRequest request = createHashRequest(plaintextBytes);
        return hashService.computeHash(request);
    }
Constructs a new PasswordService with a default hash service and the default
algorithm name {@value #DEFAULT_HASH_ALGORITHM}, a default hash format (shiro2) and
a default hash format factory.

<p>The default algorithm can change between minor versions and does not introduce
API incompatibility by design.</p>
core/src/main/java/org/apache/shiro/authc/credential/DefaultPasswordService.java