cascadeList is lost on complex callbacks

[martinaubele]

We have a complex scenario:

Server 1 calls service on server 3 Server 3 calls back to server 1 and here we do a call to server 2 before returning Server 3 calls now again server 1 and here we get a problem:

in com.atomikos.icatch.imp.CoordinatorStateHandler.setCascadeList(Map<String, Integer>) the cascadeList_ is overriden by the last 'allParticipants'. We loose the cascade entry for the call to server 1 here.

During prepare of server 2 we get then a NullPointerException:

java.lang.NullPointerException: null at com.atomikos.remoting.twopc.AtomikosRestPort.prepare(AtomikosRestPort.java:134) ~[transactions-remoting-6.0.1-SNAPSHOT.jar:na]

the Line 134 is: part.setGlobalSiblingCount(count); count is null as the cascadeList has no entry for server 2

Tested with 6.0.1-SNAPSHOT and older versions.

In my pull request you will find 3 adaptions that we need for recursive calls (Server 1 calls Server 2 and Server 2 calls back to Server 1)- The adaptions are done in ParticipantAdapter, CoordinatorImp and DefaultExportingTransactionManager. These fixes are well tested and are used in a complex production environment for a long time.

The fix for this NullPointerException is simple, i just merge the cascade maps in CoordinatorStateHandler :

protected void setCascadeList ( Map<String, Integer> allParticipants )
{
    // we merge the maps and override values in cascadeList_
    // if we dont merge we get a problem with callbacks
    if (cascadeList_ != null) { 
        **cascadeList_.putAll(allParticipants);**
    }
    else {
        cascadeList_ = allParticipants;
    }
}

Pull request containing fixes for recursive calls and a fix for the NullPointerException: https://github.com/atomikos/transactions-essentials/pull/187

To reproduce the error you have to start 3 sample applications in this repo: https://github.com/martinaubele/transactions-over-rest-with-hybrid-jaxrs-stack/tree/cascadeListBug Please do first a maven install on my pull request https://github.com/atomikos/transactions-essentials/pull/187 because you need fixes to enable recursive calls. If you want to see the NullPointerException please change the code in CoordinatorStateHandler back to

protected void setCascadeList ( Map<String, Integer> allParticipants )
{
     cascadeList_ = allParticipants;
}