Transient (and harmless?) exception when starting JOSM in java.awt.image.ColorModel

[avar]

Every once in a while I get this exception when starting JOSM:

Uncaught error fetching image:
java.lang.ClassCastException: [I cannot be cast to [B
	at java.awt.image.ColorModel.getAlpha(ColorModel.java:815)
	at java.awt.image.ColorModel.getRGB(ColorModel.java:860)
	at sun.awt.image.ImageRepresentation.convertToRGB(ImageRepresentation.java:278)
	at sun.awt.image.ImageRepresentation.setPixels(ImageRepresentation.java:494)
	at ava.awt.image.AreaAveragingScaleFilter.accumPixels(AreaAveragingScaleFilter.java:196)
	at java.awt.image.AreaAveragingScaleFilter.setPixels(AreaAveragingScaleFilter.java:235)
	at sun.awt.image.ImageDecoder.setPixels(ImageDecoder.java:108)
	at sun.awt.image.PNGImageDecoder.sendPixels(PNGImageDecoder.java:540)
	at sun.awt.image.PNGImageDecoder.produceImage(PNGImageDecoder.java:460)
	at sun.awt.image.InputStreamImageSource.doFetch(InputStreamImageSource.java:246)
	at sun.awt.image.ImageFetcher.fetchloop(ImageFetcher.java:172)
	at sun.awt.image.ImageFetcher.run(ImageFetcher.java:136)

The message appears before JOSM starts loading plugins.

It doesn't seem to have any effect on the operation of JOSM, and normally goes away when I start it again.

This has been going on for a while, like for the last 300-400 SVN revisions. Filing it because I couldn't find an existing bug.

[stoecker]

Sometimes the loading of certain PNG images issues this. It is always a different image and in my opinion always an error. I already did a web search but found no real reason. I know this error since I know JOSM.

[stoecker]

Ticket #4607 has been marked as a duplicate of this ticket.