Java Reference
In-Depth Information
Solution
Construct a
FileReader
,
FileWriter
,
FileInputStream
, or
FileOutputStream
.
Discussion
The action of constructing a
FileReader
,
FileWriter
,
FileInputStream
, or
FileOut-
putStream
corresponds to the “open” operation in most I/O packages. There is no explicit
open operation, perhaps as a kind of rhetorical flourish of the Java API's object-oriented
design. Therefore, to read a text file, you'd create, in order, a
FileReader
and a
BufferedReader
. To write a file a byte at a time, you'd create a
FileOutputStream
and
probably a
BufferedOutputStream
for efficiency:
// OpenFileByName.java
BufferedReader is = new BufferedReader(new FileReader("myFile.txt"));
BufferedOutputStream bytesOut = new BufferedOutputStream(
new FileOutputStream("bytes.dat"));
...
bytesOut.close( );
Remember that you need to handle
IOException
s around these calls.
Copying a File
Problem
You need to copy a file in its entirety.
Solution
Use a pair of
Stream
s for binary data, or a
Reader
and a
Writer
for text, and a
while
loop
to copy until end-of-file is reached on the input.
