weave all: ConcurrentModificationException

[Matthias Schoettle]

When a "weave all" is performed, a ConcurrentModificationException is thrown in the Preprocessor. It seems that this does not happen all the time, so it might not be easily reproducible. For example, when weaving StockExchange at the point of "Weaving ParallelExecution into StockExchange" the following stack trace is given:

java.util.ConcurrentModificationException
    at java.util.HashMap$HashIterator.nextEntry(HashMap.java:793)
    at java.util.HashMap$KeyIterator.next(HashMap.java:828)
    at ca.mcgill.sel.ram.weaver.structuralview.PreProcessor.createSkeletonClasses(PreProcessor.java:405)
    at ca.mcgill.sel.ram.weaver.structuralview.StructuralViewWeaver.weave(StructuralViewWeaver.java:91)
    at ca.mcgill.sel.ram.weaver.RAMWeaver.weaveSingle(RAMWeaver.java:201)
    at ca.mcgill.sel.ram.weaver.RAMWeaver.weaveAllTopDown(RAMWeaver.java:112)
    at ca.mcgill.sel.ram.ui.runner.WeaverRunner.run(WeaverRunner.java:86)

[Matthias Schoettle]

The reason is that in createSkeletonClasses there is an iteration over toAdd, and later, something is removed and added to this hashmap which causes the exception. Maybe it is enough to use an iterator?

https://bitbucket.org/mcgillram/touchram/src/0e77adc47629ce220888886ce99dd59316282817/ca.mcgill.sel.ram.weaver/src/ca/mcgill/sel/ram/weaver/structuralview/PreProcessor.java?at=master#cl-439

[Matthias Schoettle]

It also happens in weaveAllButtomUp as the instantiations are removed once woven. If it is not removed, it happens in updateInstantiationDeclaratives:

at ca.mcgill.sel.ram.weaver.structuralview.PostProcessor.updateInstantiationDeclaratives(PostProcessor.java:77)
    at ca.mcgill.sel.ram.weaver.structuralview.StructuralViewWeaver.weave(StructuralViewWeaver.java:99)
    at ca.mcgill.sel.ram.weaver.RAMWeaver.weaveSingle(RAMWeaver.java:194)
    at ca.mcgill.sel.ram.weaver.RAMWeaver.weaveAllBottomUp(RAMWeaver.java:170)

[Wisam Al Abed]

Just pushed a new branch with the fix for this issue looks like i dont get this issue anymore.

[Wisam Al Abed]

commited fix for this exception switched to iterators