SEVERE: JGRP000019: failed passing message to receiver: %s

Question

I'm trying to multicast a Serializable object containing a number of ResultSets using JGroups. The object appears to be received ok as this if statement is followed:

if(msg.getObject() instanceof State)

However when I try to run an operation on a ResultSet that this object contains, I get a NullPointer exception at this line:

while(rs.next()) {

Here is the stack trace:

Dec 10, 2013 3:08:41 PM org.jgroups.logging.JDKLogImpl error
SEVERE: JGRP000019: failed passing message to receiver: %s
java.lang.NullPointerException
    at AuctionImpl.receiveState(AuctionImpl.java:413)
    at AuctionImpl.receivePrivateMessage(AuctionImpl.java:335)
    at AuctionImpl.access$100(AuctionImpl.java:9)
    at AuctionImpl$1.receive(AuctionImpl.java:49)
    at org.jgroups.JChannel.up(JChannel.java:738)
    at org.jgroups.stack.ProtocolStack.up(ProtocolStack.java:1019)
    at org.jgroups.stack.Protocol.up(Protocol.java:409)
    at org.jgroups.protocols.FRAG2.up(FRAG2.java:182)
    at org.jgroups.protocols.FlowControl.up(FlowControl.java:434)
    at org.jgroups.stack.Protocol.up(Protocol.java:409)
    at org.jgroups.protocols.pbcast.STABLE.up(STABLE.java:294)
    at org.jgroups.protocols.UNICAST3.removeAndDeliver(UNICAST3.java:791)
    at org.jgroups.protocols.UNICAST3.handleDataReceived(UNICAST3.java:703)
    at org.jgroups.protocols.UNICAST3.up(UNICAST3.java:381)
    at org.jgroups.protocols.pbcast.NAKACK2.up(NAKACK2.java:600)
    at org.jgroups.protocols.BARRIER.up(BARRIER.java:103)
    at org.jgroups.protocols.VERIFY_SUSPECT.up(VERIFY_SUSPECT.java:147)
    at org.jgroups.protocols.FD.up(FD.java:255)
    at org.jgroups.protocols.FD_SOCK.up(FD_SOCK.java:301)
    at org.jgroups.protocols.MERGE2.up(MERGE2.java:209)
    at org.jgroups.protocols.Discovery.up(Discovery.java:379)
    at org.jgroups.protocols.TP.passMessageUp(TP.java:1399)
    at org.jgroups.protocols.TP$MyHandler.run(TP.java:1585)
    at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:895)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:918)
    at java.lang.Thread.run(Thread.java:680)

Can someone please let me know what I could be doing wrong to get that error?

Answer 1

Please use Util.objectFromByteBuffer(msg.getBuffer()) to deserialize your object first and then perform any operation.