In a Java project which uses Jersey as the REST client, there’s some warning message while it runs:

Today I found a program cannot append log to log file as usual, and there is no any error. I’m pretty sure I didn’t change anything about the logger configuration of the program yesterday. So weird.

When I wanted to make a hash instance’s content be sorted by key’s dictionary order, I found a problem.

From here, here and here.

From here.

From here.

From here.