this.artifacts = new IdentityHashMap<>();
        this.transfers = new IdentityHashMap<>();
    }

    @Override
    public void debug(String message) {}

    @Override
    public void transferCompleted(TransferEvent transferEvent) {
        ArtifactTransferEvent event = wrap(transferEvent);

        Long transferred;
        synchronized (transfers) {

    /**
     * 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.
     */
    public static final int TRANSFER_PROGRESS = 3;

    /**
     * An error occurred during transfer
     */