Double Standard?

Japan is one of the strongest proponents of increasing pressure on North Korea through the use of sanctions. This is aimed primarily at getting North Korea to acquiesce to Japan's demands about the abductee issue, not the nuclear issue which Japan seems to view as a secondary problem. Naturally, the people who will suffer most from sanctions unless they are very carefully done are the North Korean people.

Japan has taken a much different approach to Sri Lanka. Some donor countries have cut off aid, but Japan is not one of them.

The Japanese envoy said that while the human rights violations were too numerous and not in the least acceptable for a civilised country (as opposed to "uncivilized" countries? Name one.) like Sri Lanka, the people of the island should not have to suffer the consequences of their leaders’ policies.
“Our help is for victims of the conflict. People should not be punished for actions or policies of their leaders.”
Short article here.

And here.