Section 11 : The java.io Package
Describe
the permanent effects on the file system of
constructing and using FileInputStream,
FileOutputStream, and RandomAccessFile objects.
FileInputStream
Creating
an object of this class does not have any effect on
the file system. When you try to use the object for
reading the file it represents, it opens the file for
reading if the file exists. Attempts to use this
object may throw FileNotFoundException if the file
does not exist, is a directory or for some other
reason cannot be opened for reading.
FileOutputStream
Creating
an object of this class opens the file it represents,
to write to the file. If the file does not exist, a
new file is created for writing. Attempts to use this
object may throw FileNotFoundException if the file
exists but is a directory rather than a regular file,
does not exist but cannot be created, or cannot be
opened for any other reason.
RandomAccessFile
The mode
argument in its constructor must either be equal to
“r” or “rw”, indicating that the file is to be opened
for input only or for both input and output,
respectively. The write methods on this object will
always throw an IOException if the file is opened with
a mode of “r”. If the mode is “rw” and the file does
not exist, then an attempt is made to create it.
An IOException is thrown if the file argument refers
to a directory. These constructors will throw
IllegalArgumentException if mode is not “r” or “rw”.
If file exists but is a directory, or cannot be opened
or created for any other reason.
section11-1 | section11-2 | section11-3 | section11-4 | section11-5 | section11-6
Sections :
1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11
|