[SNMP4J] some SNMP4j issues...

[Renato Araújo Ferreira]

Hello all,

I´m trying to use snmp4j in my application. It worked fine for single 
threaded application, but I found some problems in a multithreaded 
environment.

Each thread has your own session initialized with:

    TransportMapping transporteUDP = new DefaultUdpTransportMapping();
    this.sessaoSNMP = new Snmp(transporteUDP);
    this.sessaoSNMP.listen();

And closed with:

    this.sessaoSNMP.close();

These sessions are reused in all thread's life cycle only changing their 
CommunityTarget and UserTarget. But, at end of process, one last target 
(randomly, not the same) always wait too many time, between 250 and 300 
seconds, in method org.snmp4j.Snmp.get with this stack:

    "DefaultUDPTransportMapping_1.1.0.160/0" daemon prio=1 tid=0x086b8070 
nid=0x7c51 runnable [0x8b948000..0x8b948ec0]
            at java.net.PlainDatagramSocketImpl.receive0(Native Method)
            at 
java.net.PlainDatagramSocketImpl.receive(PlainDatagramSocketImpl.java:136)
            - locked <0x926b9918> (a java.net.PlainDatagramSocketImpl)
            at java.net.DatagramSocket.receive(DatagramSocket.java:712)
            - locked <0xb1b6d400> (a java.net.DatagramPacket)
            - locked <0x926bacd0> (a java.net.DatagramSocket)
            at 
org.snmp4j.transport.DefaultUdpTransportMapping$ListenThread.run(Unknown 
Source)
            at java.lang.Thread.run(Thread.java:595)
            at org.snmp4j.util.DefaultThreadFactory$WorkerThread.run(Unknown 
Source)

    "Coletando: public at 00-18-F3-C7-71-05" daemon prio=1 tid=0x086244d8 
nid=0x7c38 in Object.wait() [0x8c76a000..0x8c76ae40]
            at java.lang.Object.wait(Native Method)
            - waiting on <0x92ae9730> (a 
org.snmp4j.Snmp$SyncResponseListener)
            at java.lang.Object.wait(Object.java:474)
            at org.snmp4j.Snmp.send(Unknown Source)
            - locked <0x92ae9730> (a org.snmp4j.Snmp$SyncResponseListener)
            at org.snmp4j.Snmp.send(Unknown Source)
            at org.snmp4j.Snmp.get(Unknown Source)
            ...

Sometimes I'm getting a "IllegalArgumentException: port out of range:555555" 
error with this stack:

    java.lang.IllegalArgumentException: port out of range:555555
            at java.net.InetSocketAddress.<init>(InetSocketAddress.java:83)
            at 
org.snmp4j.transport.DefaultUdpTransportMapping.sendMessage(Unknown Source)
            at org.snmp4j.MessageDispatcherImpl.sendMessage(Unknown Source)
            at org.snmp4j.MessageDispatcherImpl.sendPdu(Unknown Source)
            at org.snmp4j.Snmp.sendMessage(Unknown Source)
            at org.snmp4j.Snmp$PendingRequest.run(Unknown Source)
            at java.util.TimerThread.mainLoop(Timer.java:512)
            at java.util.TimerThread.run(Timer.java:462)

And, finally, sometimes I'm getting a "ConcurrentModificationException" 
error using a iterator (method Iterator.next()) at end of process, when all 
the SNMP communications are already finished. This code was already there 
before I'm using SNMP4j and, as I found some information about bugs like 
this in the web, I think so that could be something with my implementation 
of SNMP4j.

OMG, a large email, but could someone help me??

Thankss....

Renato A. Ferreira