Based o a command economy that produces by fiat. The bubble will burst. Supply has outstripped demand. Prices for new homes are comparable to US new housing costs in major markets. Low income housing is being replaced upscale leaving the average worker without adequate housing. Because the economy is not based on demand it does not meet the needs of the citizenry. This is leading to disruption among the poor (read middle class) and a steady devaluation of the Yen.
China as the largest economy is a ruse. It is so because the Central Committee says it is so, not because it has grown naturally based on economic forces.
That must be why they had protests back this past June in Hong Kong for that reason.