Teemu Ruskola has a decent overview at SSRN (in a pre-print of a chapter of a new comparative law text) of the Chinese, Korean, Japanese and Northern Vietnamese pre-Western legal traditions, all of which are derivative of China's legal system to some extent I recall studying basically the same concepts and materials, with slightly less historical detail, fewer Latin terms of comparative law, and less geographic specificity when I was in junior high school, and that perspective has been largely confirmed by what I have learned since then.
Key concepts include a Confucian hiearchical foundation to international tributary relationships, domestic political philosophy and personal relationships, supplemented by legalistic harsh penalties for violations of moral codes. In general, there were only weak distinctions between judicial and legal spheres, and more general administrative and governmental duties. Law per se, we not starkly distinguished from ruling a territory or a group of people, in general. Relationships were primary over rationally formulated rules applicable to all which had more of a customary or non-state character within families and guild. A lack of a clear line between conduct that is discouraged and conduct that is "illegal" in many cases, also supports are more gradual approach to escalating community/state intervention as individuals grow gradually more distant from ideals of moral conduct. The focus was on obligations that arose out of enduring and unequal relationships rather than on the rights of individual persons who were equal in legal dignity to each other.
The situation in China was somewhat akin to the very early days following the Norman Conquest in England when general purpose feudal lords presided in a general capacity to resolve disputes between their subjects on the basis of reason and local custom. And where, these aristocrats ruling from their place within a feudal hierarchy held places recently assigned to them by merit because their fiefs were awarded to them based upon their military service (or necessity for pacifying the locals) during the recent conquest, even though that ideal would be short lived and was soon replaced by a more specialized and bureaucratized legal order in which the hereditary principle would become pre-eminent.
Regional variation within this intellectual sphere hinged mostly on issues of centralization and meritocracy.
Korea was the most centralized of these East Asian states, followed by China which had a strongly centralized core with declining levels of control as one reached the fringes of its influence (and in practice, it recognized greater regional diversity that its ideological basis supposed), with Shogun Japan and Vietnam exaulting their feudal and decentralized system of small states as more reflective of the early Chinese environment in which Confucianism arose. The distinctions are somewhat analogous to those between Hamiltonian and Jeffersonian political ideologies in American history.
China was the most meritocratic of the four states, followed perhaps by the Vietnamese, while Korea retained a significant degree of aristocratic privilege apart from examination determined merit, and Japan also retained significant decrees of aristrocratic caste concepts.
Somewhat disappointingly, Ruskola does not discuss how this deeper legal tradition has managed to meld and subvert what are superficially Western communist, common law, and civil law legal and political regimes in a manner distinctly molded by this shared deeper legal tradition. South Korea, Vietnam and Japan all have statutes modeled primarily on European civil codes, with some Anglo-American glosses in the criminal justice area and a few other legal subjects in Japan and South Korea, and a Chinese communist gloss in Vietnam. But, the way that those systems work in practice is dramatically different from either the European civilian or American models. And, the form of communism practiced in China and Vietnam is likewise only barely recognizable as having shared roots with the political and legal system of the pre-Cold War Soviet block of Eastern Europe.
The Chinese political legacy was in many ways a more natural fit the the political theory that self-described communists tried to implement in Russia and Eastern Europe where it originated. Singapore and Hong Kong, both of which share both traditional Chinese and English common law roots, produced dramatically different results in their respective city states: Singapore produced a totalitarian dictatorship friendly to organized business; while Hong Kong produced a non-democratic yet libertarian leaning free for all of lassiez-faire economics with rulers who were content not to be fully in control of their domain. None of these systems wholeheartedly embrace the sort of singleminded zealous advocacy in legal disputes that is so characteristic of the American legal and political culture.