Details
-
Bug
-
Status: Resolved
-
Major
-
Resolution: Won't Fix
-
2.3
-
None
-
None
Description
When using a single FopFactory to create multiple Fop instances that are used in different threads I get an ConcurrentModificationException in ImageCache#doInvalidURIHouseKeeping in line 294.
Source of the problem is the that new HashSet(this.invalidURIs.keySet()) internaly iterates over the key-set that is backed by the HashMap and when another thread changes the HashMap the ConcurrentModificationException occurs.
In my opinion there must be synchronized-blocks around each access of the invalidURIs map to solve this problem. The use of a synchronized map can not solve this problem.
Stacktrace:
Caused by: java.util.ConcurrentModificationException: null
at java.util.HashMap$HashIterator.nextNode(HashMap.java:1437)
at java.util.HashMap$KeyIterator.next(HashMap.java:1461)
at java.util.AbstractCollection.addAll(AbstractCollection.java:343)
at java.util.HashSet.<init>(HashSet.java:119)
at org.apache.xmlgraphics.image.loader.cache.ImageCache.doInvalidURIHouseKeeping(ImageCache.java:294)
at org.apache.xmlgraphics.image.loader.cache.ImageCache.doHouseKeeping(ImageCache.java:290)
at org.apache.xmlgraphics.image.loader.cache.ImageCache.considerHouseKeeping(ImageCache.java:280)
at org.apache.xmlgraphics.image.loader.cache.ImageCache.registerInvalidURI(ImageCache.java:209)
at org.apache.xmlgraphics.image.loader.cache.ImageCache.needImageInfo(ImageCache.java:130)
at org.apache.xmlgraphics.image.loader.ImageManager.getImageInfo(ImageManager.java:123)
at org.apache.fop.fo.flow.ExternalGraphic.bind(ExternalGraphic.java:81)
at org.apache.fop.fo.FObj.processNode(FObj.java:126)
at org.apache.fop.fo.FOTreeBuilder$MainFOHandler.startElement(FOTreeBuilder.java:291)
at org.apache.fop.fo.FOTreeBuilder.startElement(FOTreeBuilder.java:179)
The issue XGC-30 sounds similiar but does not solve the problem.