AssertionException poll() is blocking call cant be called on Service thread

Question

I'm getting this:
Exception in thread "main" (Wrapped: Failed request execution for DistributedCache service on Member(Id=1, Timestamp=2009-07-16 15:23:58.704,
Address=192.168.10.167:8088, MachineId=25255, Location=machine:box2,process:4700, Role=CoherenceServer)) com.tangosol.util.AssertionException: poll()
is a blocking call and cannot be called on the Service thread
     at com.tangosol.util.Base.ensureRuntimeException(Base.java:293)
     at com.tangosol.coherence.component.util.daemon.queueProcessor.service.Grid.tagException(Grid.CDB:36)
     at com.tangosol.coherence.component.util.daemon.queueProcessor.service.grid.DistributedCache.onPutRequest(DistributedCache.CDB:66)
     at com.tangosol.coherence.component.util.daemon.queueProcessor.service.grid.DistributedCache$PutRequest.run(DistributedCache.CDB:1)
     at com.tangosol.coherence.component.net.message.requestMessage.DistributedCacheKeyRequest.onReceived(DistributedCacheKeyRequest.CDB:12)
     at com.tangosol.coherence.component.net.message.requestMessage.distributedCacheKeyRequest.ExtendedKeyRequest.onReceived(ExtendedKeyRequest.CDB:4)
     at com.tangosol.coherence.component.util.daemon.queueProcessor.service.Grid.onMessage(Grid.CDB:9)
     at com.tangosol.coherence.component.util.daemon.queueProcessor.service.Grid.onNotify(Grid.CDB:136)
     at com.tangosol.coherence.component.util.daemon.queueProcessor.service.grid.DistributedCache.onNotify(DistributedCache.CDB:3)
     at com.tangosol.coherence.component.util.Daemon.run(Daemon.CDB:37)
     at java.lang.Thread.run(Thread.java:619)
Caused by: com.tangosol.util.AssertionException: poll() is a blocking call and cannot be called on the Service thread
     at com.tangosol.coherence.Component._assertFailed(Component.CDB:12)
     at com.tangosol.coherence.Component._assert(Component.CDB:3)
     at com.tangosol.coherence.component.util.daemon.queueProcessor.service.Grid.poll(Grid.CDB:4)
     at com.tangosol.coherence.component.util.daemon.queueProcessor.service.Grid.poll(Grid.CDB:11)
     at com.tangosol.coherence.component.util.daemon.queueProcessor.service.grid.DistributedCache$BinaryMap.containsKey(DistributedCache.CDB:24)
     at com.tangosol.util.ConverterCollections$ConverterMap.containsKey(ConverterCollections.java:1494)
     at com.tangosol.coherence.component.util.daemon.queueProcessor.service.grid.DistributedCache$ViewMap.containsKey(DistributedCache.CDB:1)
     at com.tangosol.coherence.component.util.SafeNamedCache.containsKey(SafeNamedCache.CDB:1)
     at oms.ExecutionMapTrigger.process(ExecutionMapTrigger.java:22)
     at com.tangosol.coherence.component.util.daemon.queueProcessor.service.grid.DistributedCache$Storage.processTriggers(DistributedCache.CDB:12)
     at com.tangosol.coherence.component.util.daemon.queueProcessor.service.grid.DistributedCache$Storage.put(DistributedCache.CDB:30)
     at com.tangosol.coherence.component.util.daemon.queueProcessor.service.grid.DistributedCache.onPutRequest(DistributedCache.CDB:37)
     ... 8 moreIt's caused by doing a CacheFactory.getCache(...) inside a MapTrigger's process(MapTrigger.Entry entry) method. Is there some other way I can access a cache from another cache's MapTrigger? My MapTrigger looks like this. The idea of course is that when new Executions are placed in the cache, Coherence updates a Position in the positions cache in response to this event.
public class ExecutionMapTrigger implements MapTrigger {
    public ExecutionMapTrigger() {
    InvocableMap.EntryProcessor positionFillProc = new PositionFillProcessor();
    public void process(MapTrigger.Entry entry) {
        Execution e = (Execution)entry.getValue();
        Position.connectToCache(); // CacheFactory.getCache("positions");
        PositionKey positionKey = new PositionKey(e.getSymbol(), e.getAccount());
        if (!Position.cache.containsKey(positionKey)) {
           System.out.println("\tNEW position: " + e.getAccount() + " " + e.getSymbol()  );
           Position p = new Position();
           p.setSymbol(e.getSymbol());
           p.setAccount(e.getAccount());
           Position.cache.put(positionKey, p);
        } else {
           System.out.println("\tEXISTING position: " + e.getAccount() + " " + e.getSymbol() + " " + Position.cache.get(positionKey));
        Position.cache.invoke(positionKey, positionFillProc);
    // ---- hashCode() and equals() must be implemented
    public boolean equals(Object o) {
        return o != null && o.getClass() == this.getClass();
    public int hashCode() {
        return getClass().getName().hashCode();
}Is there a different way I should be doing this? Using a BackingMapListener?
Thanks,
Andrew

Answer 1

I am also stuck with similar issue. I used a backingmap listener and wanted to transformation on the data sent by the client. I am unable to update another cache.
     CoherenceTransformer transformer= new CoherenceTransformer();
          TransformedTransactionData transformedRecord = new TransformedTransactionData() ;
          ReconTransformedRecord reconTransformedRecord = new ReconTransformedRecord();
     //     NamedCache cache = CacheFactory.getCache("TxnData_TransformedRecordCache");
          System.out.println(" < <<<< Entry Inserted in ImportRecord Cache>>>>");
     //     PivotCreationListener pivotcreator ;
          ReconImportRecord i = (ReconImportRecord) event.getNewValue();
          if (logger.isDebugEnabled()) {
               logger.debug(i.getImportRecord().toString());
          transformedRecord = (TransformedTransactionData) transformer.transform((TransactionData) i.getImportRecord(),transformedRecord);
          if (logger.isDebugEnabled()) {
               logger.debug(transformedRecord.toString());
          reconTransformedRecord.setKey(i.getKey());
          reconTransformedRecord.setTransformedRecord(transformedRecord);
          System.out.println(reconTransformedRecord);
     Thread thread = new Thread(new ProcessorThread(reconTransformedRecord));
          thread.start();
2010-10-26 05:22:34.171/43.280 Oracle Coherence GE 3.6.0.0 <Warning> (thread=DistributedCache:PartitionedPofCache, member=1): Application code running on "PartitionedPofCache" service thread(s) should not call ensureCache as this may result in deadlock. The most common case is a CacheFactory call from a custom CacheStore implementation.
2010-10-26 05:22:34.171/43.281 Oracle Coherence GE 3.6.0.0 <Error> (thread=DistributedCache:PartitionedPofCache, member=1): Assertion failed: poll() is a blocking call and cannot be called on the Service thread
     at com.tangosol.coherence.component.util.daemon.queueProcessor.service.Grid.poll(Grid.CDB:5)
     at com.tangosol.coherence.component.util.daemon.queueProcessor.service.Grid.poll(Grid.CDB:11)
     at com.tangosol.coherence.component.util.daemon.queueProcessor.service.grid.partitionedService.PartitionedCache.ensureCache(PartitionedCache.CDB:29)
     at com.tangosol.coherence.component.util.daemon.queueProcessor.service.grid.partitionedService.PartitionedCache.ensureCache(PartitionedCache.CDB:36)
     at com.tangosol.coherence.component.util.safeService.SafeCacheService.ensureCache$Router(SafeCacheService.CDB:1)
     at com.tangosol.coherence.component.util.safeService.SafeCacheService.ensureCache(SafeCacheService.CDB:33)
     at com.tangosol.net.DefaultConfigurableCacheFactory.ensureCache(DefaultConfigurableCacheFactory.java:875)
     at com.tangosol.net.DefaultConfigurableCacheFactory.configureCache(DefaultConfigurableCacheFactory.java:1231)
     at com.tangosol.net.DefaultConfigurableCacheFactory.ensureCache(DefaultConfigurableCacheFactory.java:290)
     at com.tangosol.net.CacheFactory.getCache(CacheFactory.java:735)
     at com.tangosol.net.CacheFactory.getCache(CacheFactory.java:712)
     at com.xxx.listeners.ProcessorThread.<init>(ProcessorThread.java:10)
Few Questions
How do i start a thread that is not involved with service thread ?
How do I directly update a backingmap. Some example would help.