China is not Taiwan. I don't think mainland Chinese ships are under threat from water cannons. Therefore counter measures are not necessary. Little countries would be careful in getting physical with bigger countries.
Nonsense. The chinese ships had not been spray by water canon from the Japanese side does not mean that the Japanese will not do it. And who say little countries must be careful in getting physical with bigger countries? Don't ever forget that behind Japan, there is a US and nobody know what the US would or would not do yet.
Plus at the time of the water canons started spraying, the mainland Chinese government ships are not around. While the Japanese coast guards are not actually spraying water at ROC coast guards, but the fishing boats.
Finally, if the Japanese are spraying water at the Chinese fishing boats, what is the CHinese going to do about it even when a government ship is near? I think the Chinese will response in kind like the ROC, and they will be spraying water back.