File APIs for Java Developers
Manipulate DOC, XLS, PPT, PDF and many others from your application.
The moose likes Programmer Certification (SCJP/OCPJP) and the fly likes I/O Big Moose Saloon
  Search | Java FAQ | Recent Topics | Flagged Topics | Hot Topics | Zero Replies
Register / Login
JavaRanch » Java Forums » Certification » Programmer Certification (SCJP/OCPJP)
Bookmark "I/O" Watch "I/O" New topic


Lancy Mendonca
Ranch Hand

Joined: Aug 08, 2000
Posts: 54
I am thoroughly confused between FileReader and FileInputStream. From what I understand the former is char oriented stream and the latter is byte oriented. What is the difference between the two.
I wrote a small example
FileWriter fr = new FileWriter("C:/Test/Test.txt");
BufferedWriter br = new BufferedWriter(fr);
for (int i = 0; i< 5; i++)
Assuming FileReader is char oriented it outputs a char which is 2 bytes in size. However the size of the file is 5
I replaced the FileReader by a FileInputStream and still the size is 5.
Many Thanks

Sun Certified Java Programmer<BR>Oracle Certified DBA
Ajith Kallambella

Joined: Mar 17, 2000
Posts: 5782
Few text editors currently support Unicode text entry. Perhaps the text editor you used to create the file C:/Test/Test.txt supports only ASCII characters, which are limited to 7 bits.
Remember that FileReader and FileWriter read and write 16-bit characters. However, most native file systems are based on 8-bit bytes. These streams encode the characters as they operate according to the default character-encoding scheme. You can find out the default character-encoding by using System.getProperty("file.encoding"). To specify an encoding other than the default, you should construct an OutputStreamWriter on a FileOutputStream and specify it.
Try writing to a file with a non-default encoding scheme and then see how many bytes are written.

Open Group Certified Distinguished IT Architect. Open Group Certified Master IT Architect. Sun Certified Architect (SCEA).
I agree. Here's the link:
subject: I/O
It's not a secret anymore!