class PasswordComponentImpl implements PasswordComponent {

    private final Map<String, char[]> passwords;

    public PasswordComponentImpl() {
        this.passwords = new ConcurrentHashMap<>();
    }

    @Override
    public void put(String dbmsName, char[] password) {
        requireNonNull(dbmsName);
        if (password == null) {
            passwords.remove(dbmsName);
        } else {
            passwords.put(dbmsName, password);
        }
    }

    @Override
    public Optional<char[]> get(String dbmsName) {<FILL_FUNCTION_BODY>}
}

        requireNonNull(dbmsName);
        final char[] value = passwords.get(dbmsName);
        if (value == null) {
            return Optional.empty();
        } else {
            return Optional.of(value);
        }
    
<no_super_class>