buffered i/o

[slurper]

i tried this program (attached at end) but it puzzles me a little bit. The
program waits for a user to type something and immediately writes what user
writes to a file. But when i interrupt this program after having typed
something, the file is empty. What happens here: does java do buffering
automatically or is it because java interpreter didn't have chance to close
the file normally? i'd expect everything i typed before interrupting the
program, to be in the file.

import java.io.*;

public class TextFileOutput_App1 {

public static void main(String args[]) {

File file = null;
if( args.length > 0) file = new File(args[0]);
if( file == null ) {
System.out.println("Default: textOutput.txt");
file = new File("textOutput.txt");
}

// Read the bytes directly and count them.

try {
int tmp = 0;
FileWriter fileWriter = new FileWriter( file );
// Read characters from the console and write
// to the file.
while ( (tmp=System.in.read()) != -1 ) {
// Write one character at a time to the file.
fileWriter.write( (char) tmp );
}

fileWriter.close();
}
catch (IOException e) {
System.out.println( "IO error:" + e );
}
// Compare to the File class value.
System.out.println("File.length() = " + file.length() );
}
}

[Nathan Zumwalt]

You probably need to do a fileWriter.flush() before you call fileWriter.close().

I would hope Java would do some buffering, performance would be horrible otherwise.

//Nathan

slurper <sl*********@skynet.be> wrote in message news:<41**********************@news.skynet.be>...

i tried this program (attached at end) but it puzzles me a little bit. The
program waits for a user to type something and immediately writes what user
writes to a file. But when i interrupt this program after having typed
something, the file is empty. What happens here: does java do buffering
automatically or is it because java interpreter didn't have chance to close
the file normally? i'd expect everything i typed before interrupting the
program, to be in the file.

import java.io.*;

public class TextFileOutput_App1 {

public static void main(String args[]) {

File file = null;
if( args.length > 0) file = new File(args[0]);
if( file == null ) {
System.out.println("Default: textOutput.txt");
file = new File("textOutput.txt");
}

// Read the bytes directly and count them.

try {
int tmp = 0;
FileWriter fileWriter = new FileWriter( file );
// Read characters from the console and write
// to the file.
while ( (tmp=System.in.read()) != -1 ) {
// Write one character at a time to the file.
fileWriter.write( (char) tmp );
}

fileWriter.close();
}
catch (IOException e) {
System.out.println( "IO error:" + e );
}
// Compare to the File class value.
System.out.println("File.length() = " + file.length() );
}
}