[CAMEL-21376] UseOriginalAggregationStrategy - null pointer

• Type: Bug
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 4.8.0
• Fix Version/s: 4.8.2, 4.9.0
• Component/s: came-core
• Estimated Complexity: Moderate
• Assignee: Unassigned
• Reporter: Grzegorz Rozanski
• Created: 23/Oct/24 09:54
• Updated: 27/Oct/24 11:46
• Resolved: 27/Oct/24 11:46

Description

I found a case when NullPointerException occurs in 
UseOriginalAggregationStrategy's aggregate method.
 
I have this route configuration:

.multicast(AggregationStrategies.useOriginal()).parallelProcessing()
.to(DIRECT_ROUTE1)
.to(DIRECT_ROUTE2) 

 
and in the DIRECT_ROUTE2 there is:

 
.doTry() 
.unmarshal().zipFile()

When the zip file is invalid there's exception handling in UseOriginalAggregationStrategy::aggregate method:
 

exception = checkCaughtException(oldExchange, newExchange);
if (exception != null) {
    if (original != null) {
        original.setProperty(Exchange.EXCEPTION_CAUGHT, exception);
    } else {
        oldExchange.setProperty(Exchange.EXCEPTION_CAUGHT, exception);   //NULL POINTER oldExchange is null
    }
} 

 
I checked javadoc about this aggregate method it says that:
Params:
oldExchange - the oldest exchange (is null on first aggregation as we only have the new exchange)
 
and I think this is what happens in my case when I get NullPointerException in line 78 (oldExchange is null):
 

 } else {
      oldExchange.setProperty(Exchange.EXCEPTION_CAUGHT, exception);
}
 

When I create my own aggregation strategy based on UseOriginalAggregationStrategy and modify this `else` part everything works properly:
 

} else if (oldExchange != null) {
      oldExchange.setProperty(Exchange.EXCEPTION_CAUGHT, exception);
}

 
I see that similar null check already exists in checkCaughtException method.
 
 The full stack trace can be found as attachment to this ticket.

This error does not happen on Camel 4.4.0.

Issue Links

• links to: GitHub Pull Request #16093