KafkaSpout throws NoClassDefFoundError for log4j

Question

For some reason I get the following error when I try to run my topology on a Storm cluster:

java.lang.NoClassDefFoundError: Could not initialize class org.ap         


        

Answer 1

I have occured to the same problem when I included kafka like you, so I included kafka by another way according to the throw exception:

SLF4J: Detected both log4j-over-slf4j.jar AND slf4j-log4j12.jar on the class path, preempting StackOverflowError. SLF4J: See also http://www.slf4j.org/codes.html#log4jDelegationLoop for more details.

You can include kafka in the following way:

        org.apache.kafka
        kafka_2.10
        ${kafka.version}
        
            
                org.apache.zookeeper
                zookeeper
            
            
                org.slf4j
                slf4j-log4j12
            
            
            log4j
            log4j