Re: Writing unit tests for Kafka code

[Oliver Dain]

Hi Jun,

Thanks for getting back to me. Unfortunately, I can't seem to get 
KafkaServerTestHarness to work for me. I've looked around the internet for 
examples but can't find any in Java. My Java compiler seems to think that 
KafkaServerTestHarness isn't a class so it won't let me instantiate one or 
subclass it (which seems to be what the Scala code I've found is doing). For 
example, the following produce errors:


import kafka.integration.KafkaServerTestHarness;


public class KafkaReaderTest {
    @Test
    public void testHarness() {
        // Gives the error: "kafka.integration.KafkaServerTestHarness is 
abstract; cannot be instantiated"
        KafkaServerTestHarness testHarness = new KafkaServerTestHarness();
   }
}


And this:


// Produces the error, "no interface expected here"

public class TestKafkaCluster extends KafkaServerTestHarness {

}


So my compiler sometimes thinks it's an abstract class and sometimes thinks 
it's an interface. It can't be an interface or I don't think it will do 
anything for me. Additionally, the Scala code I've seen seem to be calling 
super.setUp to get things running and that wouldn't work if 
KafkaServerTestHarness was, in fact, an interface.

Some example Java code would be very much appreciated!


Thanks,

Oliver

> You can take a look at Kafka's unit tests. See how
> kafka.integration.KafkaServerTestHarness is being used.


> Thanks,
> Jun