@Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (o == null || getClass() != o.getClass()) return false;

        RecommendRelationship that = (RecommendRelationship) o;

        if (productEnd != null ? !productEnd.equals(that.productEnd) : that.productEnd != null) return false;
        if (productStart != null ? !productStart.equals(that.productStart) : that.productStart != null) return false;

        return true;
    }