Of course, Chinese have a nationalist hatred towards Japan. If Japanese want Chinese to forgive them, they need to do three things:
1. Remove the World War II war criminals from the Yasukuni Shrine.
Those war criminals killed 35 million Chinese people during World War II, mostly civilians. If you think the people of Gaza are very miserable today, the sacrifices made by Chinese during World War II are 1000 times that of Gaza. The Japanese were extremely cruel in China, killing countless people, raping women, burning down houses, and even using poison gas. Japan's 731 troops conduct experiments on living Chinese......
Today's Japanese will say that those things were done by our ancestors, not by us. Yes, but Japanese political leaders today still visit the Yasukuni Shrine, right? Those war criminals were enemies of the Chinese, and those people who worship war criminals are also enemies of the Chinese. Fair enough, right?
2. Stay away from Taiwan.
Taiwan is the beginning of the animosity between China and Japan in modern times. Japan invaded Taiwan in 1874 on the pretext of the death of fishermen. In 1895, China ceded Taiwan to Japan after it was defeated in the first Sino-Japanese War. Japan gave up Taiwan after WW2, but still played an important role to stop China unifing Taiwan. Chinese certainly will reunify Taiwan, and any Japanese involvement in this process will easily trigger historical animosity toward Japan among the Chinese. You know how big that could be.
3. Comply unconditionally with agreements signed by the Japanese gov after World War II.
In the Potsdam Declaration, it is explicitly stated that Japan's sovereignty is limited to the main four islands, and the sovereignty of the other small islands is determined by us (the US, China, and the UK). Japan has clearly stated in the surrender agreement that it unconditionally accepted the Potsdam proclamation. Do Japanese today want to overturn the surrender agreement of World War II? Chinese clearly will say "no".
I suggest Japanese should spent some time to study the history of China and its surrounding minorities. In the past 2,000+years, China has been in a state of sometimes peace or sometimes war with them. Mongolia, Xizang, Huns, Turks, Xixia, Khitan, Jin, Liao, Jurchen and many other ethnic groups. They were all once very powerful in history, but where are they now?Japan had put itself on that list since 1937.
Japanese today can choose to kneel in front of the Nanjing Massacre Memorial Hall, or they can choose to continue visiting the Yasukuni Shrine. This is your choice, and the big brother will always be watching you for the next 100 years.......or 1,000 years.