China carrier was bought as scrape from Ukraine and towed back to China as it doesn't had any propulsion system. It was berth at the dock in Dalian for a number of years before China managed to overcome the technical obstacles to refurbish it themselves.
There is a different between how India and China approach towards arm procurement. India buy arms purely as an end user. Because India doesn't achieve high degree of self sufficiency in manufacturing of high tech weaponry, she needs to get it from international market. But to prevent herself from being held political ransom from a single supplier, she needs to diversify the source of weapons from Israel, Russia, US, Europe etc This results in huge logistical and integration problems.
China don't have the luxury of multiple weapon supplies due to arm embargo. Her doctrine has always been about self sufficiency and only import equipments that their local industry cannot produce. And when China needs to buy, they can only turn to Russia and Ukraine which often result in less favorable sales terms for China. But the intention is to import weapons to study, absorb and eventually produce it themselves.
China bought fighter jets and missiles from Russia for the purpose of studying the plane to do reverse engineering and from there absorb and improve on the original design. As a result they are able to produce clones of Russian equipments and even compete with Russia in international market much to the anger of the Russians.