root@sapphire$ export DISPLAY="localhost:1.0"
root@sapphire$ /usr/X11R6/bin/Xvfb :1 -screen 0 1024x768x8 &
[1] 23058
root@sapphire$ PEXExtensionInit: Couldn't open default PEX font file  Roman_M
Could not init font path element /usr/X11R6/lib/X11/fonts/CID/, removing from list!
root@sapphire$

public class Jpeg{
    public static void main(String[] args) throws IOException{
        InputStream in = new BufferedInputStream(new FileInputStream(args[0]));
        JPEGImageDecoder decoder = JPEGCodec.createJPEGDecoder(in);
        BufferedImage img = decoder.decodeAsBufferedImage();
        BufferedImage icon = new BufferedImage(100, 100, BufferedImage.TYPE_INT_RGB);
        Graphics g = icon.getGraphics();
        g.drawImage(img.getScaledInstance(100, 100, Image.SCALE_SMOOTH), 0, 0, null);
        FileOutputStream out = new FileOutputStream(args[1]);
        JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(out);
        encoder.encode(icon);
        out.flush();
        out.close();
        in.close();
        return;
    }
}

root@sapphire$ java Jpeg img.1.jpg img.2.jpg
Warning: Cannot convert string "-watanabe-mincho-medium-r-normal--*-140-*-*-c-*-jisx0208.1983-0" to type FontStruct
PEXExtensionInit: Couldn't open default PEX font file  Roman_M
Could not init font path element /usr/X11R6/lib/X11/fonts/CID/, removing from list!
root@sapphire$ ps aux
USER       PID %CPU %MEM   VSZ  RSS TTY      STAT START   TIME COMMAND
…
root     23058  0.0  0.6  7612 3528 pts/0    S    17:50   0:00 /usr/X11R6/bin/Xvfb :1 -screen 0 1024x768x8
…
root@sapphire$

#!/bin/bash
#
# chkconfig: - 91 35
# description: Starts and stops XVfb. \
#              used to provide virtual frame buffer.

# Source function library.
. /etc/init.d/functions

prog=$"Xvfb"

# Xvfb program
XVFB=/usr/X11R6/bin/Xvfb

start() {
    echo -n $"Starting $prog: "
    daemon /usr/X11R6/bin/Xvfb :1 -screen 0 1024x768x24 &
    echo
}

stop() {
    echo -n $"Shutting down $prog: "
    killproc Xvfb
    echo
}

# See how we were called.
case "$1

root@sapphire$ chmod 755 xvfb
root@sapphire$ ./xvfb start
Xvfbを起動中:                                              [  OK  ]
root@sapphire$ ps -ef | grep Xvfb
root      3100  3099  0 05:53 pts/0    00:00:00 /usr/X11R6/bin/Xvfb :1 -screen 0
root@sapphire$ ./xvfb stop
Xvfbを停止中:                                              [  OK  ]
root@sapphire$

root@sapphire$ chkconfig --add xvfb
root@sapphire$ chkconfig xvfb on
root@sapphire$ chkconfig --list
…
xvfb            0:オフ  1:オフ  2:オフ  3:オン  4:オン  5:オン  6:オフ
…
root@sapphire$

…
#
#   JSSE_HOME       (Optional) May point at your Java Secure Sockets Extension
#                   (JSSE) installation, whose JAR files will be added to the
#                   system class path used to start Tomcat.
#
# $Id: index.html,v 1.1 2004/11/04 16:44:05 torao Exp $
# -----------------------------------------------------------------------------
DISPLAY="localhost:1.0"
export DISPLAY

# OS specific support.  $var _must_ be set to either true or false.
cygwin=false
case "`uname`" in
CYGWIN*) cygwin=true;;
esac
…