event.setDataLength(length);
        event.setTransferredBytes(transferred);

        listener.transferProgress(event);
    }

    @Override
    public void transferStarted(TransferEvent transferEvent) {
        listener.transferStarted(wrap(transferEvent));
    }

    private ArtifactTransferEvent wrap(TransferEvent event) {
        if (event == null) {
            return null;
        } else {

public interface ArtifactTransferListener {
    boolean isShowChecksumEvents();

    void setShowChecksumEvents(boolean showChecksumEvents);

    void transferInitiated(ArtifactTransferEvent transferEvent);

    void transferStarted(ArtifactTransferEvent transferEvent);

    void transferProgress(ArtifactTransferEvent transferEvent);

    void transferCompleted(ArtifactTransferEvent transferEvent);

    /**
     * A transfer was attempted, but has not yet commenced.
     */
    public static final int TRANSFER_INITIATED = 0;

    /**
     * A transfer was started.
     */
    public static final int TRANSFER_STARTED = 1;

    /**
     * A transfer is completed.
     */
    public static final int TRANSFER_COMPLETED = 2;

    /**
     * A transfer is in progress.
     */