SYNOPSIS
--------
Cannot customise font configuration with Java 7 on Linux

OPERATING SYSTEM
----------------
Linux

FULL JDK VERSION
----------------
Java 7 onwards

PROBLEM DESCRIPTION
-------------------
We are unable to customize logical fonts with Java 7 on Linux.

With Java 6 we are able to customize the fontconfig.properties file, but with Java 7 we are not able to customize the fontconfig.properties files, as per the following documentation:

--------
Support for Linux and Solaris 11 fonts

Historically, the logical fonts for the JDK were statically specified in a fontconfig.properties file. However, on the various implementations of Linux, there is no consistency in the presence of fonts. So, without custom files, Asian (CJK) text, etc, would not be rendered. In JDK 7, on Linux, and for Solaris 11, in the absence of a customized fontconfig.properties file for the OS version, the default behavior is to use the system libfontconfig to select fonts to use for the logical fonts. In this case, the logical fonts will reflect the fonts used by the Gnome/KDE desktop applications which use the same platform library. For more information, see Fontconfig on freedesktop.org.
--------
http://docs.oracle.com/javase/7/docs/webnotes/adoptionGuide/index.html#swing

This documentation states that for operating systems which do no have a customized fontconfig.properties file, logical fonts will be defined by libfontconfig. However, if we make changes to the OS font configuration those changes are not picked up by the JDK.

TESTCASE
--------
import java.awt.*;

public class TestFonts extends Canvas {
    public static void main (String args[]) {
        TestFonts tf = new TestFonts();
        tf.doit();
    }

    public TestFonts() {
    }

    public void doit() {
        Font font = new Font("Monospaced", Font.PLAIN, 12);
        FontMetrics fm = getFontMetrics(font);
        int[] widths = fm.getWidths();
        int charWidth = widths[65]; // Y8741 use 'A' char for width calculation
        int charHeight = fm.getHeight();
        int charDescent = fm.getDescent();
        System.out.println("family="+font.getFamily()+",name="+font.getFontName());
        System.out.println("charWidth ="+charWidth+" charHeight="+charHeight+" charDescent="+charDescent);
    }
}

REPRODUCTION INSTRUCTIONS
-------------------------
The following tests assume that your Linux installation has the font "Courier New" located at /usr/share/fonts/courier/cour.ttf.

Test 1: Confirm customized fontconfig.properties does not work in Java 7
========================================================================

1. Run class TestFonts, expected output: (exact output may vary)

   # /jre/bin/java TestFonts
   family=Monospaced,name=Monospaced.plain
   charWidth =7 charHeight=15 charDescent=3

2. Backup and remove /jre/lib/fontconfig.*

3. Create the file:

   /jre/lib/fontconfig.<OS version>.properties
   
   with the contents below. We were running on SUSE 11, so I created the
   file "fontconfig.SuSE.11.properties".

   --------
   version 1

   monospaced.plain.latin-1=-monotype-courier new-medium-r-normal--*-%d-*-*-m-*-iso8859-1

   sequence.allfonts=latin-1

   awtfontpath.latin-1=/usr/share/fonts/courier/cour.ttf
   --------

4. Run class TestFonts and note that the value of charWidth, charHeight,
   charDescent is the same as step 1 => fontconfig.properties does not
   change the phyiscal font of "Monospaced"

EXPECTED:
   # /jre/bin/java TestFonts
   family=Monospaced,name=Monospaced.plain
   charWidth =7 charHeight=14 charDescent=4

ACTUAL:
   # /jre/bin/java TestFonts
   family=Monospaced,name=Monospaced.plain
   charWidth =7 charHeight=15 charDescent=3


Test 2: Confirm libfontconfig changes are not picked up by Java 7, in the absence of a customized fontconfig.properties file
===================================================================================


1. Run class TestFonts, expected output: (exact output may vary)

   # /jre/bin/java TestFonts
   family=Monospaced,name=Monospaced.plain
   charWidth =7 charHeight=15 charDescent=3

2. Create ~/.fonts.conf with the following contents:

   --------
   <?xml version="1.0"?>
   <!DOCTYPE fontconfig SYSTEM "fonts.dtd">
   <fontconfig>
           <alias binding="strong">
                   <family>Monospaced</family>
                   <prefer>
                           <family>Courier New</family>
                   </prefer>
           </alias>
   </fontconfig>
   --------

3. Run fc-match to verify libfontconfig should select "Courier New" for
   monospace

   # fc-match monospace
   cour.ttf: "Courier New" "Normal"

4. Run class TestFonts and note that the value of charWidth, charHeight,
   charDescent is the same as step 1 => OS libfontconfig settings do not
   change the phyiscal font of "Monospaced"

EXPECTED:
   # /jre/bin/java TestFonts
   family=Monospaced,name=Monospaced.plain
   charWidth =7 charHeight=14 charDescent=4

ACTUAL:
   # /jre/bin/java TestFonts
   family=Monospaced,name=Monospaced.plain
   charWidth =7 charHeight=15 charDescent=3