[COCOON-2340] XMLByteStreamCompiler in not thread-safe

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 2.2
• Component/s: * Cocoon Core
• Urgency: Normal
• Affects version (Component): Components: Pipeline - 1.0.0
• Assignee: Javier Puerto
• Reporter: Ivan Lagunov
• Created: 27/Nov/13 14:55
• Updated: 30/Nov/13 14:27

Description

I'm periodically getting the following exceptions in different places:

Caused by: java.lang.ArrayIndexOutOfBoundsException
        at java.lang.System.arraycopy(Native Method)
        at org.apache.cocoon.components.sax.XMLByteStreamCompiler.getSAXFragment(XMLByteStreamCompiler.java:61)
        at org.apache.cocoon.components.pipeline.impl.ExpiresCachingProcessingPipeline.processXMLPipeline(ExpiresCachingProcessingPipeline.java:152)

After debugging I've found the root cause. It happens due to multi-threading when one thread allocates newbuf array, then another thread increments bufCount in write method and then the first thread fails on System.arraycopy invocation.

I suggest making getSAXFragment and write methods synchronized. It should resolve the issue. If it helps, I'll provide a patch later.