I have defined a KafkaReceiver usind WSO2-CEP in management console. It doesn't work and I can read this error on server-console log
[2016-02-26 10:17:25,412] INFO {org.wso2.carbon.event.input.adapter.core.internal.InputAdapterRuntime} - Connecting receiver kafkaReceiver
[2016-02-26 10:17:25,415] ERROR {org.wso2.carbon.event.input.adapter.core.internal.InputAdapterRuntime} - Error initializing Input Adapter 'kafkaReceiver, hence this will be suspended indefinitely, Cannot access kafka context due to missing jars
org.wso2.carbon.event.input.adapter.core.exception.InputEventAdapterRuntimeException: Cannot access kafka context due to missing jars
at org.wso2.carbon.event.input.adapter.kafka.KafkaEventAdapter.createConsumerConfig(KafkaEventAdapter.java:114)
at org.wso2.carbon.event.input.adapter.kafka.KafkaEventAdapter.createKafkaAdaptorListener(KafkaEventAdapter.java:132)
at org.wso2.carbon.event.input.adapter.kafka.KafkaEventAdapter.connect(KafkaEventAdapter.java:66)
at org.wso2.carbon.event.input.adapter.core.internal.InputAdapterRuntime.start(InputAdapterRuntime.java:72)
at org.wso2.carbon.event.input.adapter.core.internal.InputAdapterRuntime.startPolling(InputAdapterRuntime.java:62)
at org.wso2.carbon.event.input.adapter.core.internal.CarbonInputEventAdapterService.startPolling(CarbonInputEventAdapterService.java:187)
at org.wso2.carbon.event.receiver.core.internal.CarbonEventReceiverService.startPolling(CarbonEventReceiverService.java:620)
at org.wso2.carbon.event.receiver.core.internal.CarbonEventReceiverManagementService.startPolling(CarbonEventReceiverManagementService.java:99)
at org.wso2.carbon.event.processor.manager.core.internal.CarbonEventManagementService$2.run(CarbonEventManagementService.java:184)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
at java.util.concurrent.FutureTask.run(FutureTask.java:262)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(ScheduledThreadPoolExecutor.java:178)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:292)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.NoClassDefFoundError: kafka/consumer/ConsumerConfig
at org.wso2.carbon.event.input.adapter.kafka.KafkaEventAdapter.createConsumerConfig(KafkaEventAdapter.java:112)
... 15 more
Caused by: java.lang.ClassNotFoundException: kafka.consumer.ConsumerConfig cannot be found by org.wso2.carbon.event.input.adapter.kafka_5.0.3
at org.eclipse.osgi.internal.loader.BundleLoader.findClassInternal(BundleLoader.java:501)
at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:421)
at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:412)
at org.eclipse.osgi.internal.baseadaptor.DefaultClassLoader.loadClass(DefaultClassLoader.java:107)
at java.lang.ClassLoader.loadClass(ClassLoader.java:358)
... 16 more
If we read the class source at this link https://github.com/wso2/carbon-analytics-common/blob/master/components/event-receiver/event-input-adapters/org.wso2.carbon.event.input.adapter.kafka/src/main/java/org/wso2/carbon/event/input/adapter/kafka/KafkaEventAdapter.java
I read that the error is in ConsumerConfig creation