Kafka is just delivering raw content (byte[], String), so you'll need to parse the JSON, e.g., with Jackson or another JSON processing library.
— [email protected] | Multifarious, Inc. | http://mult.ifario.us/ On Thu, Mar 12, 2015 at 1:31 PM, Sowjanya.Kakarala < [email protected]> wrote: > > > Hi All > > > > I am trying to take the Json data from OpaqueTridentKafkaSpout, and I have > only one input field is json.However I am not sure how to take this input > field in my case because if I take an input field like > > > > Fields field = new Fields(“json”); it throws an error saying the following: > > > > Exception in thread "main" java.lang.IllegalArgumentException: Trying to > select non-existent field: 'json' from stream containing fields fields: > <[str]> > > at > storm.trident.Stream.projectionValidation(Stream.java:373) > > at storm.trident.Stream.each(Stream.java:140) > > at > com.target.bigred.storm.trident.TridentTopo.main(TridentTopo.java:233) > > at sun.reflect.NativeMethodAccessorImpl.invoke0(Native > Method) > > at > sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) > > at > sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) > > at java.lang.reflect.Method.invoke(Method.java:606) > > at > com.intellij.rt.execution.application.AppMain.main(AppMain.java:134) > > > > Can someone please help me how to take the input fields in trident? > > I appreciate your help.Thanks. > > Thanks > > Sowjanya > > >
