L Bunny

Correction:
It should be BufferedWriter and FileChannel

I have this code (BufferedReader) to write data that I read from a table to an output file.
ResultSet rs = stmt.executeQuery(); File outputDir = new File(sysObj.getOutputFileDirectory()); if (!outputDir.exists()) { outputDir.mkdir(); } String file = "out.csv"; String fileDetails = sysObj.getOutputFileDirectory().concat(file); BufferedWriter bw = new BufferedWriter(new FileWriter(fileDetails)); while (rs.next()) { for (int i = 1; i <= neededList.size(); i++) { Object o = rs.getObject(i); bw.write(o == null ? "" : o.toString()); bw.write("|"); } bw.newLine(); } bw.flush(); bw.close();
8 records are retrieved from a table and it tooks 00:00:01.40300 to write to an output file and the output file size is 3KB.

Then, i use FileChannel to do the same thing. But it tooks 00:00:01.63200 to write to an output file and the outfile file size is 2151KB
ResultSet rs = stmt.executeQuery(); File outputDir = new File(sysObj.getOutputFileDirectory()); if (!outputDir.exists()) { outputDir.mkdir(); } String file = "out.csv"; String fileDetails = sysObj.getOutputFileDirectory().concat(file); FileOutputStream outputFile = null; try { outputFile = new FileOutputStream(fileDetails, true); System.out.println("File stream created successfully."); } catch (FileNotFoundException e) { e.printStackTrace(System.err); } FileChannel outChannel = outputFile.getChannel(); ByteBuffer buf = null; while (rs.next()) { String phrase = null; for (int i = 1; i <= neededList.size(); i++) { Object o = rs.getObject(i); phrase = o == null ? "" : o.toString(); buf = ByteBuffer.allocate((phrase).length()); buf.put(phrase.getBytes()); phrase = "|"; buf = ByteBuffer.allocate((phrase).length()); buf.put(phrase.getBytes()); } phrase = "\n"; buf = ByteBuffer.allocate((phrase).length()); buf.put(phrase.getBytes()); buf.flip(); } outChannel.write(buf); outputFile.close();
Question:-
1. There is no way for me to pre-allocate ByteBuffer size because I won't know the size until i read the value of a column from ResultSet, right?

2. Should I make a conclusion that BufferedWriter is better than FileChannel when reading data from a table and writing it to an output file? If I am wrong, can someone please help to correct my mistake by providing some source code to modify my FileChannel source code?

Thanks to all the guru and experts 1st.
[ November 27, 2007: Message edited by: Jim Yingst ]