Should KFilterDev::readData() and writeData() be protected access?

[Richard Dale]

In QIODevice the readData() and writeData() pure virtual methods have 
protected access:

protected:
#ifdef QT_NO_QOBJECT
    QIODevice(QIODevicePrivate &dd);
#else
    QIODevice(QIODevicePrivate &dd, QObject *parent = 0);
#endif
    virtual qint64 readData(char *data, qint64 maxlen) = 0;
    virtual qint64 readLineData(char *data, qint64 maxlen);
    virtual qint64 writeData(const char *data, qint64 len) = 0;

KFilterDev subclasses QIODevice, and implements these methods with access 
public, but shouldn't they be protected?

-- Richard