[BATIK-695] svggen Font fails to load Arial Unicode in Batik 1.6

• Type: Bug
• Status: Resolved
• Resolution: Cannot Reproduce
• Affects Version/s: 1.6
• Component/s: SVGGraphics2D
• Environment: Operating System: Windows XP; Platform: All
• Assignee: Batik Developer's Mailing list
• Reporter: Peter Farland
• Created: 28/Feb/07 11:02
• Updated: 28/Feb/07 20:23
• Resolved: 28/Feb/07 20:23

Description

Here's the stacktrace:

java.lang.NegativeArraySizeException
at org.apache.batik.svggen.font.table.HmtxTable.init(HmtxTable.java:59)
at org.apache.batik.svggen.font.Font.read(Font.java:178)
at org.apache.batik.svggen.font.Font.create(Font.java:196)

If I had to take a guess at a solution, from that stacktrace it appears Batik
failed to read a value for numberOfHMetrics from the HHEA table in the TTF. I
took a quick look at the TTF specification from Microsoft and it appears this
value is an unsigned short:

http://www.microsoft.com/OpenType/OTSpec/hhea.htm

...however, Apache Batik is reading it in as a normal Java short (which is
signed) on line 58 of org.apache.batik.svggen.font.table.HheaTable. The huge
number of glyph entries in Arial Unicode probably means the number of entries in
the HMTX table exceeds 32768 hence the short wraps around to a negative value,
and thus the initialization of the hMetrics Array fails. Using an int to store
this value and correcting for the negative bit with a mask should solve the problem.

Note that we think we've successfully run tests with Arial Unicode in the past,
so perhaps this is a regression in Batik 1.6?