I observed very strange problem, when I open a file using new
FileInputStream() and then close this stream, and then try to delete or
rename it OS Windows reports:
The process cannot access the file because it is being used by another

I'm sorry of this question has been posed and answered many times before.
But I have avoided using the "package" statement because of this.
Most of my classes have no "package" statement, and their class files are
stored in my current directory.  Using "javac abc.java" works just ...

I need to synchronize 4 different threads.  I dont think wait() and
notifyall() will work.
Could someone explain how to do this?
Jerry