final String[] sourceFiles = records.keySet().toArray(new String[records.size()]);
Arrays.sort(sourceFiles);
for (int i = 0; i < sourceFiles.length; i++)
{
final String sourceFile = sourceFiles[i];
final FontRecord fontRecord = records.get(sourceFile);
final FontMetrics metrics = metricsFactory.createMetrics(fontRecord.getIdentifier(), context);
writer.writeTag(null, "font-source", "source", sourceFile, false);
/*
<global-metrics ascent="0" descent="0" italic-angle="0" leading="0"
max-ascent="0" max-char-advance="0" max-descent="0" max-height="0"