Unlike Russia, China has the Ability to manufacture advanced fighter jets in mass numbers.China is the only major oil importer that dares to buy Iranian oil and do business with iran directly or indirectly.Personally, Selling J10 is a bit risky. If it is not matched with AWACS HQ-9B, and HQ-19 will not form a system. If it is matched with them, not to mention the funds, the Iranian government has been infiltrated like a sieve, and the data of the AWACS will immediately become shared by the US and Israel but u have to start from somewhere. Iran needs to take its own internal security seriously maybe work with chinese intelligence agency to root out mossad agents.