I am really confused about the purpose of various io classes, for example, If we have BufferedWriter, why we need a PrintWriter?
BufferedReader reader = new Buff
They have nothing to do with each other. In all truth, I rarely use PrintWriter
except to convert System.out
temporarily. But anyway.
BufferedWriter
, like BufferedReader
/BufferedInputStream
/BufferedOutputStream
merely decorates the enclosed Writer
with a memory buffer (you can specify the size) or accept a default. This is very useful when writing to slow Writers like network or file based. (Stuff is committed in memory and only occasionally to disk for example) By buffering in memory the speed is greatly increased - try writing code that writes to say a 10 mb file with just FileWriter
and then compare to the same with BufferedWriter
wrapped around it.
So that's BufferedWriter
. It throws in a few convenience methods, but mostly it just provides this memory buffer.
PrintWriter
mostly is a simple decorator that adds some specific write methods for various types like String
, float
, etc, so you don't have to convert everything to raw bytes.
Edited:
This already has come up