Hi, I want to simulate a network failure between Zookeeper clients and a Zookeeper server. I try to use Mina to implement a proxy to an Apache Zookeeper process, but I get strange exceptions. My route definition looks like this:
<beans xmlns="http://www.springframework.org/schema/beans"; xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"; xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://camel.apache.org/schema/spring http://camel.apache.org/schema/spring/camel-spring.xsd";> <camelContext id="camelZookeeperProxyContext" xmlns="http://camel.apache.org/schema/spring";> <route id="ZookeeperTCP_1_Proxy"> <from id="zookeeper1Proxy" uri="mina:tcp://localhost:2282?sync=true&allowDefaultCodec=false"/> <to id="zookeeper1Target" uri="mina:tcp://localhost:2182?sync=true&allowDefaultCodec=false"/> </route> </camelContext> </beans> So I am trying to forward requests sent to port 2282 to 2182, but it fails: ----%< snip %<------------------- output on proxy ------------------%< snip %<----- ... [2011-06-22 10:52:12][TRACE][Camel (camelZookeeperProxyContext) thread #3 - MinaThreadPool][org.apache.camel.management.InstrumentationProcessor] - route: Recording duration: 60 millis for exchange: Exchange[Message: DirectBuffer[pos=0 lim=40 cap=1024: 00 00 00 24 00 00 00 00 00 00 75 30 01 30 B6 65 49 10 00 02 00 00 00 10 9C 3A B1 12 E7 04 3B 20 86 CC B8 B8 A1 F0 67 4B]] [2011-06-22 10:52:12][TRACE][Camel (camelZookeeperProxyContext) thread #3 - MinaThreadPool][org.apache.camel.impl.DefaultUnitOfWork] - UnitOfWork done for ExchangeId: ID-sopmac11-50678-1308732723240-0-1 with Exchange[Message: DirectBuffer[pos=0 lim=40 cap=1024: 00 00 00 24 00 00 00 00 00 00 75 30 01 30 B6 65 49 10 00 02 00 00 00 10 9C 3A B1 12 E7 04 3B 20 86 CC B8 B8 A1 F0 67 4B]] [2011-06-22 10:52:12][TRACE][Camel (camelZookeeperProxyContext) thread #3 - MinaThreadPool][org.apache.camel.impl.DefaultInflightRepository] - Total 0 inflight exchanges. Last removed: ID-sopmac11-50678-1308732723240-0-1 [2011-06-22 10:52:12][TRACE][Camel (camelZookeeperProxyContext) thread #3 - MinaThreadPool][org.apache.camel.util.AsyncProcessorHelper] - Exchange processed and is continued routed synchronously for exchangeId: ID-sopmac11-50678-1308732723240-0-1 -> Exchange[Message: DirectBuffer[pos=0 lim=40 cap=1024: 00 00 00 24 00 00 00 00 00 00 75 30 01 30 B6 65 49 10 00 02 00 00 00 10 9C 3A B1 12 E7 04 3B 20 86 CC B8 B8 A1 F0 67 4B]] [2011-06-22 10:52:12][DEBUG][Camel (camelZookeeperProxyContext) thread #3 - MinaThreadPool][org.apache.camel.component.mina.MinaConsumer] - Writing body: DirectBuffer[pos=0 lim=40 cap=1024: 00 00 00 24 00 00 00 00 00 00 75 30 01 30 B6 65 49 10 00 02 00 00 00 10 9C 3A B1 12 E7 04 3B 20 86 CC B8 B8 A1 F0 67 4B] [2011-06-22 10:52:12][TRACE][Camel (camelZookeeperProxyContext) thread #3 - MinaThreadPool][org.apache.camel.component.mina.MinaHelper] - Waiting for write to complete [2011-06-22 10:52:12][DEBUG][Camel (camelZookeeperProxyContext) thread #3 - MinaThreadPool][org.apache.camel.component.mina.MinaConsumer] - Closing session as an exception was thrown from MINA [2011-06-22 10:52:12][WARN][Camel (camelZookeeperProxyContext) thread #3 - MinaThreadPool][org.apache.camel.component.mina.MinaConsumer$ReceiveHandler ] - [/127.0.0.1:50684] Unexpected exception from exceptionCaught handler. org.apache.camel.CamelException: java.lang.IllegalStateException: Already released buffer. You released the buffer too many times. at org.apache.camel.component.mina.MinaConsumer$ReceiveHandler.exceptionCaught (MinaConsumer.java:95) at org.apache.mina.common.support.AbstractIoFilterChain$TailFilter.exceptionCa ught(AbstractIoFilterChain.java:564) at org.apache.mina.common.support.AbstractIoFilterChain.callNextExceptionCaugh t(AbstractIoFilterChain.java:345) at org.apache.mina.common.support.AbstractIoFilterChain.access$1000(AbstractIo FilterChain.java:53) at org.apache.mina.common.support.AbstractIoFilterChain$EntryImpl$1.exceptionC aught(AbstractIoFilterChain.java:643) at org.apache.mina.filter.executor.ExecutorFilter.processEvent(ExecutorFilter. java:224) at org.apache.mina.filter.executor.ExecutorFilter$ProcessEventsRunnable.run(Ex ecutorFilter.java:264) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.j ava:886) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java: 908) at java.lang.Thread.run(Thread.java:680) Caused by: java.lang.IllegalStateException: Already released buffer. You released the buffer too many times. at org.apache.mina.common.PooledByteBufferAllocator$PooledByteBuffer.release(P ooledByteBufferAllocator.java:310) at org.apache.mina.util.ByteBufferUtil.releaseIfPossible(ByteBufferUtil.java:3 9) at org.apache.mina.common.support.AbstractIoFilterChain$TailFilter.messageRece ived(AbstractIoFilterChain.java:572) at org.apache.mina.common.support.AbstractIoFilterChain.callNextMessageReceive d(AbstractIoFilterChain.java:299) at org.apache.mina.common.support.AbstractIoFilterChain.access$1100(AbstractIo FilterChain.java:53) at org.apache.mina.common.support.AbstractIoFilterChain$EntryImpl$1.messageRec eived(AbstractIoFilterChain.java:648) at org.apache.mina.filter.executor.ExecutorFilter.processEvent(ExecutorFilter. java:220) ... 4 more [2011-06-22 10:52:12][DEBUG][Camel (camelZookeeperProxyContext) thread #3 - MinaThreadPool][org.apache.camel.component.mina.MinaConsumer] - Closing session as an exception was thrown from MINA [2011-06-22 10:52:12][WARN][Camel (camelZookeeperProxyContext) thread #3 - MinaThreadPool][org.apache.camel.component.mina.MinaConsumer$ReceiveHandler ] - [/127.0.0.1:50684] Unexpected exception from exceptionCaught handler. org.apache.camel.CamelException: java.lang.IllegalStateException: Already released buffer. You released the buffer too many times. at org.apache.camel.component.mina.MinaConsumer$ReceiveHandler.exceptionCaught (MinaConsumer.java:95) at org.apache.mina.common.support.AbstractIoFilterChain$TailFilter.exceptionCa ught(AbstractIoFilterChain.java:564) at org.apache.mina.common.support.AbstractIoFilterChain.callNextExceptionCaugh t(AbstractIoFilterChain.java:345) at org.apache.mina.common.support.AbstractIoFilterChain.access$1000(AbstractIo FilterChain.java:53) at org.apache.mina.common.support.AbstractIoFilterChain$EntryImpl$1.exceptionC aught(AbstractIoFilterChain.java:643) at org.apache.mina.filter.executor.ExecutorFilter.processEvent(ExecutorFilter. java:224) at org.apache.mina.filter.executor.ExecutorFilter$ProcessEventsRunnable.run(Ex ecutorFilter.java:264) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.j ava:886) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java: 908) at java.lang.Thread.run(Thread.java:680) Caused by: java.lang.IllegalStateException: Already released buffer. You released the buffer too many times. at org.apache.mina.common.PooledByteBufferAllocator$PooledByteBuffer.release(P ooledByteBufferAllocator.java:310) at org.apache.mina.util.ByteBufferUtil.releaseIfPossible(ByteBufferUtil.java:3 9) at org.apache.mina.common.support.AbstractIoFilterChain$TailFilter.messageSent (AbstractIoFilterChain.java:581) at org.apache.mina.common.support.AbstractIoFilterChain.callNextMessageSent(Ab stractIoFilterChain.java:320) at org.apache.mina.common.support.AbstractIoFilterChain.access$1200(AbstractIo FilterChain.java:53) at org.apache.mina.common.support.AbstractIoFilterChain$EntryImpl$1.messageSen t(AbstractIoFilterChain.java:653) at org.apache.mina.filter.executor.ExecutorFilter.processEvent(ExecutorFilter. java:222) ... 4 more [2011-06-22 10:52:12][DEBUG][Camel (camelZookeeperProxyContext) thread #3 - MinaThreadPool][org.apache.mina.filter.executor.ExecutorFilter] - Exiting since queue is empty for /127.0.0.1:50684 [2011-06-22 10:52:14][TRACE][SocketAcceptor-0][org.apache.camel.util.concurrent.Executo rServiceHelper] - Created thread[MinaSocketAcceptor]: Thread[Camel (camelZookeeperProxyContext) thread #8 - MinaSocketAcceptor,5,main] [2011-06-22 10:52:14][DEBUG][SocketAcceptorIoProcessor-0.1][org.apache.mina.filter.exec utor.ExecutorFilter] - Launching thread for /127.0.0.1:50688 [2011-06-22 10:52:14][TRACE][SocketAcceptorIoProcessor-0.1][org.apache.camel.util.concu rrent.ExecutorServiceHelper] - Created thread[MinaThreadPool]: Thread[Camel (camelZookeeperProxyContext) thread #9 - MinaThreadPool,5,main] [2011-06-22 10:52:14][DEBUG][Camel (camelZookeeperProxyContext) thread #9 - MinaThreadPool][org.apache.camel.component.mina.MinaConsumer] - Received body: DirectBuffer[pos=0 lim=48 cap=1024: 00 00 00 2C 00 00 00 00 00 00 00 00 00 00 00 00 00 00 75 30 01 30 B6 65 49 10 00 02 00 00 00 10 9C 3A B1 12 E7 04 3B 20 86 CC B8 B8 A1 F0 67 4B] [2011-06-22 10:52:14][TRACE][Camel (camelZookeeperProxyContext) thread #9 - MinaThreadPool][org.apache.camel.impl.DefaultUnitOfWork] - UnitOfWork created for ExchangeId: ID-sopmac11-50678-1308732723240-0-3 with Exchange[Message: DirectBuffer[pos=0 lim=48 cap=1024: 00 00 00 2C 00 00 00 00 00 00 00 00 00 00 00 00 00 00 75 30 01 30 B6 65 49 10 00 02 00 00 00 10 9C 3A B1 12 E7 04 3B 20 86 CC B8 B8 A1 F0 67 4B]] ... ---->% snap >%----------------- end output on proxy ---------------->% snap >%----- Is there anything obvious I am missing? Do I need a Java Implementation? Would this be easier using Netty instead of Mina? Thanks in advance Jürgen -- Jürgen Kindler
