Thanks Micah. The issue here was that I did not provide a field name for the nested child field which caused this error. As per doc I thought it was optional but doesn't work like that.
On Fri, Nov 13, 2020 at 12:12 PM Micah Kornfield <[email protected]> wrote: > Hi Saloni, > Sample code for how you are using the Arrow APIs are useful. > > Also how can I validate if the output generated by Arrow writer is in >> valid format? > > Being able to read it back would be the best mechanism here? Are you > think of unit tests or in production? Or something else? > > Thanks, > Micah > > On Wed, Nov 4, 2020 at 12:43 AM Saloni Udani <[email protected]> > wrote: > >> Hello, >> I have a use case where I want to write an arrow batch to my existing >> output stream (custom stream extending java.io.OutputStream) and reading >> from my existing input stream (custom stream extending >> java.io.InputStream). I used ArrowStreamWriter and ArrowStreamReader but >> on the reader side I get NPE while getting VectorSchemaRoot. >> >> Caused by: java.lang.NullPointerException: null >> at >> org.apache.arrow.vector.types.pojo.Field.mutateOriginalNameIfNeeded(Field.java:188) >> at org.apache.arrow.vector.types.pojo.Field.convertField(Field.java:172) >> at org.apache.arrow.vector.types.pojo.Schema.convertSchema(Schema.java:87) >> at >> org.apache.arrow.vector.ipc.message.MessageSerializer.deserializeSchema(MessageSerializer.java:201) >> at >> org.apache.arrow.vector.ipc.ArrowStreamReader.readSchema(ArrowStreamReader.java:174) >> at >> org.apache.arrow.vector.ipc.ArrowReader.initialize(ArrowReader.java:170) >> at >> org.apache.arrow.vector.ipc.ArrowReader.ensureInitialized(ArrowReader.java:161) >> at >> org.apache.arrow.vector.ipc.ArrowReader.getVectorSchemaRoot(ArrowReader.java:63) >> >> >> >> >> Kindly guide what am I doing wrong? I believe this to be an issue of IO >> streams. Is there any prerequisite to which IO streams can be used with >> Arrow reader and writer? >> >> Also how can I validate if the output generated by Arrow writer is in >> valid format? >> >> >> Regards >> Saloni Udani >> >
