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    @Override
    public int hashCode() {
        final int prime = 31;
        int result = 1;
        result = prime * result + ((cartId == null) ? 0 : cartId.hashCode());
        return result;
    }

    @Override
    public boolean equals(Object obj) {
        if (this == obj)
            return true;
        if (obj == null)
            return false;
        if (getClass() != obj.getClass())
            return false;
        Cart other = (Cart) obj;
        if (cartId == null) {
            if (other.cartId != null)
                return false;
        } else if (!cartId.equals(other.cartId))
            return false;
        return true;
    }

}