Example of Output Buffering

package com.bruceeckel;
 
import java.io.BufferedOutputStream;
import java.io.BufferedWriter;
import java.io.FileOutputStream;
import java.io.FileWriter;
import java.io.IOException;
import java.io.OutputStream;
import java.io.Writer;
 
// Buffering may speed up writes to a FileOutputStream, but not for 
// a FileWriter, because a FileWriter is
// an OutputStreamWriter, which already uses the buffering.
public class OutputStreamDemo {
    public static void main(String[] args) throws IOException {
	OutputStream os1 = new FileOutputStream("tmp1.dat");
	writeints("Unbuffered: ", 1000000, os1);
	OutputStream os2 = new BufferedOutputStream(new FileOutputStream(
		"tmp2.dat"));
	writeints("Buffered:   ", 1000000, os2);
	Writer wr1 = new FileWriter("tmp1.dat");
	writeints("Unbuffered: ", 1000000, wr1);
	Writer wr2 = new BufferedWriter(new FileWriter("tmp2.dat"));
	writeints("Buffered:   ", 1000000, wr2);
    }
 
    static void writeints(String msg, int count, OutputStream os)
	    throws IOException {
	long currentTime = System.currentTimeMillis();
	for (int i = 0; i < count; i++)
	    os.write(i & 255);
	os.close();
	System.out.println(msg
		+ Long.toString(System.currentTimeMillis() - currentTime));
    }
 
    static void writeints(String msg, int count, Writer os) throws IOException {
	long currentTime = System.currentTimeMillis();
	for (int i = 0; i < count; i++)
	    os.write(i & 255);
	os.close();
	System.out.println(msg
		+ Long.toString(System.currentTimeMillis() - currentTime));
    }
 
}