VisualVM and Self Time

Solution 1:

Self Time is a wall-clock time spent in the method itself (includes time waiting/sleeping).
Self Time (CPU) is a time processor time, so it does NOT include time spent waiting, sleeping, etc.
Both columns do NOT include time spent in methods invoked from that method.
Both Self Time and Self Time (CPU) in the sampler are approximation of actual data.
Self Time [%] refers to one of the two selected Self Time [(CPU)] columns.