The chance of having Japan to Apologise for their crime is nearly 0.
There are a lot of reason behind this, Japanese pride, Japanese stubbornness but most of all, those who committed the crime is LONG GONE
Same as a guy who murder many, many people, now he's dead, and you expect his great grandson (not even his son or grandson) to apologise for a crime committed 70 odd years ago. They don't even know what happen back then. Even if they do apologise, will it ever going to be the same as those man who do those crime apologising?
Most of "This generation" Japanese do not care about the war anymore, also goes with all the pride and responsibility with them. If you talk to a Japanese Person in Japan today and ask him what he feel about WW2. He/She will answer you as if he took the content of any WW2 drama out of the TV set. Which is not much.
You can hate them all you want, but they do not know anything about what happened 70 years ago. Not much China can do, yo ucan only say China become strong 70 years too late for an apologise.
Don't get me wrong, people have a conscience know what they did was wrong. But asking this Generation to apologise is impossible, you better sue them and get some money out of it. At least you can get them to admit to what they did 70 years ago