To better understand what an inner class is, I'd suggest reading Sun's Java Tutorial Trail on Inner Classes.
Thanks for the reminding and answer!
I have read this tutorial before. The answer of my question can not be found directly from the tutorial.
Actually I want to ask why in this if
statement the outter class name Test4
can be used to refer to the flag
. How can you know you can use this format to refer to a outter class's field variable? In which book or in which part of the sun tutorial can you find similar usage like Test4.this.flag
(I can not find a example like this in Sun's inner class tutorial)?