Europe, India, and Japan all had what one might call a "knightly" class: Aristocrats who could afford the armour, horses and training to be much more effective combatants than the peasants whose surplus they extracted. (I'm aware that I'm simplifying, but as a view-from-ten-thousand-feet I think this is reasonable.) But it seems that China did not have such a class; their hereditary aristocracy is stereotypically bureaucratic, as in passing the examinations, rather than military, as in wearing mail and keeping an armed retinue. (At least once we get out of literal chariot warfare.) Why was this? Or did China in fact have warrior-aristocrats and I'm just missing them due to the literary dominance of the bureaucrat-aristocrats?
Of course, other places had non-military aristocrats to, as clergy in Europe, Brahmins in India, but it seems that the balance of power and prestige between them is quite unusual in China. Crudely, you'd think a military class unsatisfied with its position would just whack the scholar-bureaucrats over the head with their swords and rearrange matters to their own satisfaction, but this does not seem to happen. Why not?
I believe this answer from /u/cthulhushrugged answers your question and the thread also provides a remarkable amount of sources about this stuff.
Well, China has lots of dynasties, so it depends on different dynasties.
In pre-Qin period（？-------BC 221）, referring to period before Qin Dynasty, typically Zhou Dynasty（BC 1100------BC 256）, there were the warrior-aristocrat class.
After the Zhou Dynasty replaced the Shang Dynasty（BC 1600---BC 1046）, the enfeoffment system was implemented. Except the capital area, the Zhou Dynasty enfeoffed the territory to the royal family members, aristocrats and the Shang Dynasty Royal family members. Among them, the royal family members got more fertile lands, while the aristocrats and the Shang Dynasty royal family members got less and worse lands, many of which were border areas. They had their own administrative system, tax system and military system. Apart from paying taxes to the Zhou royal family and participating in the Zhou Royal wars, they were completely independent kingdoms. These vassal states also granted their lands to their subordinates, who had the same rights and obligations as the vassal states.
In the history of China, these subordinates were called the gentry, which is what you call the warrior-aristocrat classes. At this time, the enfeoffment system in China and Europe were very similar, but the enfeoffment system of China ended before BC, and the enfeoffment system of Europe lasted after the Middle Ages.
Here comes the dynasty that ends China enfeoffment system. In Chinese mythology, the ancestors of Qin Dynasty contributed to the flood control. And they were given the surname "Ying" by Emperor Shun because they raised animals for Emperor Shun. Later the Zhou Dynasty asked them to raise horses for Zhou. Because of the merit of horse raising, the Ying family was enfeoffed into Qin region and established the Qin state.
After wars and annexation in the Seven Warring States period（Rome was in republic period.）, the state of Qin unified most of China and occupied today's North Vietnam and North Korea. First Emperor of Qin followed the advices of palace minister Li Si, abolished the enfeoffment system and adopted the centralized county system. From then on, the enfeoffment system gradually disappeared in China, and China began the centralized monarchy system for thousands of years.
Why i say the enfeoffment system die out gradually? Because after the Qin Dynasty was overthrown by the old nobles of the other six countries, the Han Dynasty（Rome became imperial.） implemented the system of county system and enfeoffment system simultaneously for a period of time. Han dynasty picked up enfeoffment system again. As a result, there was a rebellion in the Han Dynasty, which was known as "the rebellion of the seven countries" historically. After the rebellion was suppressed, Emperor Wu of the Han Dynasty implemented the "Tui En Order" to forcibly order the vassal states to enfeoffal the lands to all their heirs. In this way, there are more and more vassal states, smaller and weaker. Then Emperor Wu of the Han Dynasty used many excuses to abolish the vassal states, and finally the enfeoffment system was completely abolished in China.
At this moment the aristocracy with independent administrative system, tax system and military system completely disappeared.
Till Sui and Tang Dynasties（The rise of the Arab Caliphate Empire period）, the imperial examination system was implemented. According to this system, officials are selected through examinations, and there is a complete assessment system for their promotion, rewards and punishments, and dismissal. This completely put an end to the situation that the official positions were inherited by the aristocrats from the late Han Dynasty(AD 184----AD 220) to the Sui and Tang Dynasties(AD 581---AD 960). So the influence of military aristocracy began to be replaced by the civil bureaucrat class. After the lands are taken back, the aristocrats still controlled and influenced ancient China for nearly 400 years. By the way the PRC political system also follows this set of system, of course, after modern adjustment. So you can often see the news that China's top provincial and ministerial officials are dismissed.
This is the reason and procedure that China does not have a dominant warrior-aristocrat class.