What's the fastest way to output a string to system out?

Thank you for the suggestions. I created a test program to compare them:

import java.io.BufferedOutputStream;
import java.io.BufferedWriter;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.lang.StringBuilder;

public class systemouttest {

    public static void main(String[] args) throws Exception {

        long starttime = System.currentTimeMillis();
        for (int i = 0; i < 100000; i++) {
           System.out.println( i );
        }
        long printlntime = System.currentTimeMillis();

        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < 100000; i++) {
            sb.append( i + "\n" );
        }
        System.out.print(sb.toString());
        long stringbuildertime = System.currentTimeMillis();

        OutputStream out = new BufferedOutputStream ( System.out );
        for (int i = 0; i < 100000; i++) {
            out.write((i + "\n").getBytes());
        }
        out.flush();
        long bufferedoutputtime = System.currentTimeMillis();

        BufferedWriter log = new BufferedWriter(new OutputStreamWriter(System.out));
        for (int i = 0; i < 100000; i++) {
            log.write(i + "\n");
        }
        log.flush();
        long bufferedwritertime = System.currentTimeMillis();

        System.out.println( "System.out.println: " + (printlntime - starttime) );
        System.out.println( "StringBuilder: " + (stringbuildertime - printlntime) );
        System.out.println( "BufferedoutputStream: " + (bufferedoutputtime - stringbuildertime) );
        System.out.println( "BufferedWriter: " + (bufferedwritertime - bufferedoutputtime) );
    }

}

Results:

Environment1
System.out.println: 482
StringBuilder: 210
BufferedoutputStream: 86
BufferedWriter: 202

Environment2
System.out.println: 1763
StringBuilder: 45
BufferedoutputStream: 76
BufferedWriter: 34

The suggestions all performed better than System.out.println. BufferedOutputStream seems to be the safest choice as it performed well in both test environments. BufferedWriter maybe faster though.

Please post further suggestions if anyone has some ideas. I'm sure someone can make it go faster :)

For large amount of data,System.out.println might be inefficient as it does not do very good buffering. In that case, you can use a BufferedOutputStream or a BufferedWriter.

Keep in mind that I/O operations are very slow compared to in-memory processing (e.g. parsing of Integer). So, I would propose you to create the whole string 'in advance' and then print it out only once (of course if its possible):

StringBuilder sb = new StringBuilder();

for(int i = 0 ; i < 100000; i++) { sb.append(i).append("\n");}
String printMe = sb.toString(); 
System.out.println(printMe);

There are various techniques like buffering the the level of output stream you're using, but I assume that you prefer to stay with the most basic System.out.println

Hope this helps