Java R&W Related
In Java, byte = 8 bit, char = 16 bit
In C/C++, char = 8 bit
There is difference because Java uses Unicode, however C uses ASCII as basic character collection.
Java uses InputStream to read BYTE-DATA, to cover InputStream with InputStreamReader to read CHAR-DATA, to cover InputStreamReader with BufferedStream to read line of chars. So java have to recomprehend the byte infomation into char information and into line-chars information with a 2-step conversion.
Rembember the following:
size: 8 bit -> 16 bit -> line -> file
mode: byte -> char -> line -> file
read: IS -> ISR -> BR -> String
write: OS -> OSW ->( *BW ->) PW -> String
Why do we have the parenthesized BW part?, see the official doc:(Java SE 8)
In general, a Writer sends its output immediately to the underlying character or byte stream. Unless prompt output is required, it is advisable to wrap a BufferedWriter around any Writer whose write() operations may be costly, such as FileWriters and OutputStreamWriters. For example,
PrintWriter out
= new PrintWriter(new BufferedWriter(new FileWriter("foo.out")));
will buffer the PrintWriter's output to the file. Without buffering, each invocation of a print() method would cause characters to be converted into bytes that would then be written immediately to the file, which can be very inefficient.
When reviewing some test programs that I wrote following the java tutorial, find something like:
1 FileOutputStream out = new FileOutputStream("1.txt"); 2 //Considering using the following method instead 3 BufferedOutputStream bos = new BufferedOutputStream(new FileOutputStream("1.txt"));
Checked Java SE 8 official API, that BOS method exists! Gee.. And, that's the exact usage of BOS.. Gee again...
