@Override
	public String toString() {
		final StringBuffer buffer = new StringBuffer();

		for (int i = 0; i < headers.length; i++)
			buffer.append(headers[i] + "\t");
		buffer.append("\n");

		for (final SoldItem item : rows) {
			buffer.append(item.getId() + "\t");
			buffer.append(item.getName() + "\t");
			buffer.append(item.getPrice() + "\t");
			buffer.append(item.getQuantity() + "\t");
			buffer.append(item.getSum() + "\t");
			buffer.append("\n");
		}

		return buffer.toString();
	}