As much as I hate reference Wikipedia, thy have a good list of every apology formally issued by the Japanese government. In addition, WWII is taught in schools and most people in Japan are fully aware of the fact that Japan was the aggressor in WWII, as well as committed war crimes. There are as always outspoken nationalists who claim that Japan did nothing wrong, and in fact that Yushukan museum in Yasukuni shrine tends to contain a significant amount of extremely right-wing propaganda (such as "Japan has always valued a free an independent Korea, so they annexed it.), but this is par for the course in most countries, including Germany.

If you're talking about the shrine visits, the Japanese visits to Yasukuni Shrine are much the same as a US President visiting Arlington Cemetery. The only difference is that there are convicted war criminals among the dead enshrined at Yasukuni (although it is arguable that some of the so-called "Class A" criminals were merely executed because they failed to rein in their more bloodthirsty subordinates, and that hunting down said subordinates would have proven too difficult). Still, the move is enough to anger the Chinese and Korean governments, because due to the complicated nature of how a person's spirit is enshrined, when one visits the shrine, one honors the "kami" (god or spirit) of the shrine, which is a summation of all the Japanese war dead enshrined there. As a result, one can rightfully argue that visiting Yasukuni in an official capacity can be seen as the Japanese government condoning war crimes.