Java Reference
In-Depth Information
Exercises
1.
Modify the example that avoids overwriting a file to allow for file names that do not
have extensions.
2.
Filenames on many systems are not of unlimited length, so appending _
old
to file names may
break down at some point. Modify the example that avoids overwriting a file to append a
three-digit numerical value to the file name to differentiate it from the existing file instead of
just adding _
old
. The program should check for the presence of three digits at the end of the
name for the existing file and replace this with a value incremented by an amount to make it
unique. (That is, increment the last three digits by 1 until a unique file name is created.)
3.
Write a program that will list all the directories in a directory defined by a path supplied as a
command line argument, or all the directories on a system if no command line argument is
present. (Hint: The
listRoots()
method will give you the roots on a system and the
listFiles()
method will give you an array of
File
objects for the files and directories in
any given directory - including a root.)
