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Posted to user@avro.apache.org by Alan Miller <al...@gmail.com> on 2013/01/07 17:35:23 UTC
issue with writing an array of records
Hi, I have a schema with an array of records (I'm open to other suggestions
too) field
called ifnet to store misc attribute name/values for a host's network
interfaces.
e.g.
{ "type": "record",
"namespace": "com.company.avro.data",
"name": "MyRecord",
"doc": "My Data Record.",
"fields": [
// (required) fields
{"name": "time_stamp", "type": "long"
},
{"name": "hostname", "type": "string"
},
// (optional) array of ifnet instances
{"name": "ifnet",
"type": ["null", {
"type": "array",
"items": { "type": "record", "name": "Ifnet",
"namespace": "com.company.avro.data",
"fields": [ {"name": "name", "type":
"string"},
{"name": "send_bps", "type":
"long" },
{"name": "recv_bps", "type":
"long" }
]
}
}
]
}
]
}
I can write the records, (time_stamp and hostname are correct) but
my "array of records" field (ifnet) only contains the last element of my
java List.
Am I writing the field correctly? I'm trying to write the ifnet field with
a
java.util.List<com.company.avro.data.Ifnet>
Here's the related code lines that write the ifnet field. (Yes, I'm
attempting to use reflection
because Ifnet is only 1 of approx 11 other array of record fields I'm
trying to implement.)
Class[] paramObj = new Class[1];
paramObj[0] = Ifnet.class;
Method method = cls.getMethod(methodName, List.class);
jsonObj = new Ifnet();
listOfObj = new ArrayList<Ifnet>();
.......
// in a loop building the List<Ifnet>.......
LOG.info(String.format(" [%s] %s %s(%s) as %s", name,
k,methNm,v,types[j].toString()));
.......
LOG.info(String.format(" [%s] setting name to %s", name, name));
.......
istOfObj.add(jsonObj);
.......
// then finally I call invoke with a List of Ifnet records
if (method != null) { method.invoke(obj, listOfObj); }
LOG.info(String.format(" invoking %s.%s",
method.getClass().getSimpleName(), method.getName()));
LOG.info(String.format(" param: listObj<%s> with %d entries" ,
jsonObj.getClass().getName(), listOfObj.size()));
and the respective output
20130107T172303 INFO c.c.a.d.MyDriver - Set ifnet json
via setIfnet(Ifnet object)
20130107T172303 INFO c.c.a.d.MyDriver - [e0c] setting name to e0c
20130107T172303 INFO c.c.a.d.MyDriver - [e0c] send_bps setSendBps(0) as
class java.lang.Long
20130107T172303 INFO c.c.a.d.MyDriver - [e0c] setting name to e0c
20130107T172303 INFO c.c.a.d.MyDriver - [e0c] recv_bps setRecvBps(0) as
class java.lang.Long
20130107T172303 INFO c.c.a.d.MyDriver - [e0d] setting name to e0d
20130107T172303 INFO c.c.a.d.MyDriver - [e0d] send_bps setSendBps(0) as
class java.lang.Long
20130107T172303 INFO c.c.a.d.MyDriver - [e0d] setting name to e0d
20130107T172303 INFO c.c.a.d.MyDriver - [e0d] recv_bps setRecvBps(0) as
class java.lang.Long
20130107T172303 INFO c.c.a.d.MyDriver - [e0a] setting name to e0a
20130107T172303 INFO c.c.a.d.MyDriver - [e0a] send_bps
setSendBps(170720) as class java.lang.Long
20130107T172303 INFO c.c.a.d.MyDriver - [e0a] setting name to e0a
20130107T172303 INFO c.c.a.d.MyDriver - [e0a] recv_bps
setRecvBps(244480) as class java.lang.Long
20130107T172303 INFO c.c.a.d.MyDriver - [e0b] setting name to e0b
20130107T172303 INFO c.c.a.d.MyDriver - [e0b] send_bps setSendBps(0) as
class java.lang.Long
20130107T172303 INFO c.c.a.d.MyDriver - [e0b] setting name to e0b
20130107T172303 INFO c.c.a.d.MyDriver - [e0b] recv_bps setRecvBps(0) as
class java.lang.Long
20130107T172303 INFO c.c.a.d.MyDriver - [e0P] setting name to e0P
20130107T172303 INFO c.c.a.d.MyDriver - [e0P] send_bps setSendBps(0) as
class java.lang.Long
20130107T172303 INFO c.c.a.d.MyDriver - [e0P] setting name to e0P
20130107T172303 INFO c.c.a.d.MyDriver - [e0P] recv_bps setRecvBps(0) as
class java.lang.Long
20130107T172303 INFO c.c.a.d.MyDriver - [losk] setting name to losk
20130107T172303 INFO c.c.a.d.MyDriver - [losk] send_bps setSendBps(0)
as class java.lang.Long
20130107T172303 INFO c.c.a.d.MyDriver - [losk] setting name to losk
20130107T172303 INFO c.c.a.d.MyDriver - [losk] recv_bps setRecvBps(0)
as class java.lang.Long
20130107T172303 INFO c.c.a.d.MyDriver - invoking Method.setIfnet
20130107T172303 INFO c.c.a.d.MyDriver - param:
listObj<com.synopsys.iims.be.storage.Ifnet> with 6 entries
20130107T172303 INFO c.c.a.d.MyDriver - Set time_stamp integer
via setTimeStamp to 1357513251
When I dump the records I see an array of 6 entries but the values all
reflect the last last entry in my java.util.List.
The print statements suggest I'm passing a list of 6 items with different
values,
[amiller@localhost $] hadoop fs -copyToLocal /data/test_2013-01-07.avro
[amiller@localhost $] avro cat --fields=time_stamp,ifnet
test_2013-01-07.avro|less
{"time_stamp": 1357513251, "ifnet": [{"send_bps": 0, "recv_bps": 0,
"name": "losk"}, {"send_bps": 0, "recv_bps": 0, "name": "losk"},
{"send_bps": 0, "recv_bps": 0, "name": "losk"}, {"send_bps": 0, "recv_bps":
0, "name": "losk"}, {"send_bps": 0, "recv_bps": 0, "name": "losk"},
{"send_bps": 0, "recv_bps": 0, "name": "losk"}]}
{"time_stamp": 1357513550, "ifnet": [{"send_bps": 0, "recv_bps": 0,
"name": "losk"}, {"send_bps": 0, "recv_bps": 0, "name": "losk"},
{"send_bps": 0, "recv_bps": 0, "name": "losk"}, {"send_bps": 0, "recv_bps":
0, "name": "losk"}, {"send_bps": 0, "recv_bps": 0, "name": "losk"},
{"send_bps": 0, "recv_bps": 0, "name": "losk"}]}
Any ideas.
Alan
Re: issue with writing an array of records
Posted by Alan Miller <al...@gmail.com>.
Thanks Scott, I figured it out. The problem was simply an improper loop
design.
I corrected the loop code and now I get an array of Ifnet records.
[amiller@loclhost $] avro cat --fields hostname,ifnet data_2013-01-08.avro
{"hostname": "host08", "ifnet": [{"send_bps": 0, "recv_bps": 0, "name":
"e0P"}, {"send_bps": 171256, "recv_bps": 197512, "name": "vif1"},
{"send_bps": 0, "recv_bps": 0, "name": "vif2"}, {"send_bps": 0, "recv_bps":
0, "name": "losk"}]}
{"hostname": "host11", "ifnet": [{"send_bps": 9992353544, "recv_bps":
14049010776, "name": "e1a"}, {"send_bps": 0, "recv_bps": 0, "name": "e1b"},
{"send_bps": 2736, "recv_bps": 2960, "name": "e0P"}, {"send_bps": 9376,
"recv_bps": 19312, "name": "c0a"}, {"send_bps": 0, "recv_bps": 0, "name":
"vif1"}, {"send_bps": 9376, "recv_bps": 19312, "name": "c0b"}, {"send_bps":
0, "recv_bps": 0, "name": "e0M"}, {"send_bps": 0, "recv_bps": 0, "name":
"losk"}]}
I did not have to change my schema.
For anyone interested, I verified I could write my array of records with
the schema using this test program.
public class ArrayOfRecTest {
public static void main(String[] args) throws IOException {
String fileName = "/tmp/test.avro";
File avroFile = new File(fileName);
// NOTE: MyRecord.java was generated from MyRecord.avsc
and avro.compiler.specific.SchemaTask
Schema schema = new MyRecord().getSchema();
DatumWriter<MyRecord> writer = new SpecificDatumWriter<MyRecord>(schema);
DataFileWriter<MyRecord> dataFileWriter = new
DataFileWriter<MyRecord>(writer);
dataFileWriter.create(schema, avroFile);
MyRecord record = new MyRecord();
record.setHostname("localhost");
record.setTimeStamp(new Long(1357639723));
List<Ifnet> ifnetList = new ArrayList<Ifnet>();
Ifnet ifc1 = new Ifnet("eth0", 1234L, 5678L); ifnetList.add(ifc1);
Ifnet ifc2 = new Ifnet("eth1", 100L, 200L); ifnetList.add(ifc2);
Ifnet ifc3 = new Ifnet("eth2", 0L, 0L); ifnetList.add(ifc3);
record.setIfnet(ifnetList);
dataFileWriter.append(record);
dataFileWriter.flush();
dataFileWriter.close();
}
}
Alan
On Tue, Jan 8, 2013 at 11:36 AM, Scott Carey <sc...@apache.org> wrote:
>
> On 1/7/13 8:35 AM, "Alan Miller" <al...@gmail.com> wrote:
>
>
> >Hi, I have a schema with an array of records (I'm open to other
> >suggestions too) field
> >called ifnet to store misc attribute name/values for a host's network
> >interfaces.
> >e.g.
> >
> >
> >{ "type": "record",
> > "namespace": "com.company.avro.data",
> > "name": "MyRecord",
> > "doc": "My Data Record.",
> > "fields": [
> > // (required) fields
> > {"name": "time_stamp", "type": "long"
> > },
> > {"name": "hostname", "type": "string"
> > },
> >
> > // (optional) array of ifnet instances
> > {"name": "ifnet",
> > "type": ["null", {
> > "type": "array",
> > "items": { "type": "record", "name": "Ifnet",
> > "namespace": "com.company.avro.data",
> > "fields": [ {"name": "name", "type":
> >"string"},
> > {"name": "send_bps", "type":
> >"long" },
> > {"name": "recv_bps", "type":
> >"long" }
> > ]
> > }
> > }
> > ]
> > }
> >
> > ]
> >}
>
> First thought: Why the union of null and the array? It may be easier to
> simply have an empty list when there are no Ifnet data.
>
>
>
> >
> >
> >I can write the records, (time_stamp and hostname are correct) but
> >my "array of records" field (ifnet) only contains the last element of my
> >java List.
> >
> >Am I writing the field correctly? I'm trying to write the ifnet field
> >with a
> >java.util.List<com.company.avro.data.Ifnet>
> >
> >Here's the related code lines that write the ifnet field. (Yes, I'm
> >attempting to use reflection
> >because Ifnet is only 1 of approx 11 other array of record fields I'm
> >trying to implement.)
> >
> > Class[] paramObj = new Class[1];
> > paramObj[0] = Ifnet.class;
> > Method method = cls.getMethod(methodName, List.class);
> > jsonObj = new Ifnet();
> > listOfObj = new ArrayList<Ifnet>();
> > .......
> >
> >
> > // in a loop building the List<Ifnet>.......
> >
> > LOG.info(String.format(" [%s] %s %s(%s) as %s", name,
> >k,methNm,v,types[j].toString()));
> > .......
> >
> > LOG.info(String.format(" [%s] setting name to %s", name, name));
> >
> > .......
> >
> > istOfObj.add(jsonObj);
> >
> > .......
> >
> > // then finally I call invoke with a List of Ifnet records
> >
> > if (method != null) { method.invoke(obj, listOfObj); }
> > LOG.info(String.format(" invoking %s.%s",
> >method.getClass().getSimpleName(), method.getName()));
> > LOG.info(String.format(" param: listObj<%s> with %d entries" ,
> >jsonObj.getClass().getName(), listOfObj.size()));
> >
> >
> >and the respective output
> >20130107T172303 INFO c.c.a.d.MyDriver - Set ifnet
> >json via setIfnet(Ifnet object)
> >20130107T172303 INFO c.c.a.d.MyDriver - [e0c] setting name to e0c
> >20130107T172303 INFO c.c.a.d.MyDriver - [e0c] send_bps setSendBps(0)
> >as class java.lang.Long
> >20130107T172303 INFO c.c.a.d.MyDriver - [e0c] setting name to e0c
> >20130107T172303 INFO c.c.a.d.MyDriver - [e0c] recv_bps setRecvBps(0)
> >as class java.lang.Long
> >20130107T172303 INFO c.c.a.d.MyDriver - [e0d] setting name to e0d
> >20130107T172303 INFO c.c.a.d.MyDriver - [e0d] send_bps setSendBps(0)
> >as class java.lang.Long
> >20130107T172303 INFO c.c.a.d.MyDriver - [e0d] setting name to e0d
> >20130107T172303 INFO c.c.a.d.MyDriver - [e0d] recv_bps setRecvBps(0)
> >as class java.lang.Long
> >20130107T172303 INFO c.c.a.d.MyDriver - [e0a] setting name to e0a
> >20130107T172303 INFO c.c.a.d.MyDriver - [e0a] send_bps
> >setSendBps(170720) as class java.lang.Long
> >20130107T172303 INFO c.c.a.d.MyDriver - [e0a] setting name to e0a
> >20130107T172303 INFO c.c.a.d.MyDriver - [e0a] recv_bps
> >setRecvBps(244480) as class java.lang.Long
> >20130107T172303 INFO c.c.a.d.MyDriver - [e0b] setting name to e0b
> >20130107T172303 INFO c.c.a.d.MyDriver - [e0b] send_bps setSendBps(0)
> >as class java.lang.Long
> >20130107T172303 INFO c.c.a.d.MyDriver - [e0b] setting name to e0b
> >20130107T172303 INFO c.c.a.d.MyDriver - [e0b] recv_bps setRecvBps(0)
> >as class java.lang.Long
> >20130107T172303 INFO c.c.a.d.MyDriver - [e0P] setting name to e0P
> >20130107T172303 INFO c.c.a.d.MyDriver - [e0P] send_bps setSendBps(0)
> >as class java.lang.Long
> >20130107T172303 INFO c.c.a.d.MyDriver - [e0P] setting name to e0P
> >20130107T172303 INFO c.c.a.d.MyDriver - [e0P] recv_bps setRecvBps(0)
> >as class java.lang.Long
> >20130107T172303 INFO c.c.a.d.MyDriver - [losk] setting name to losk
> >20130107T172303 INFO c.c.a.d.MyDriver - [losk] send_bps setSendBps(0)
> >as class java.lang.Long
> >20130107T172303 INFO c.c.a.d.MyDriver - [losk] setting name to losk
> >20130107T172303 INFO c.c.a.d.MyDriver - [losk] recv_bps setRecvBps(0)
> >as class java.lang.Long
> >20130107T172303 INFO c.c.a.d.MyDriver - invoking Method.setIfnet
> >20130107T172303 INFO c.c.a.d.MyDriver - param:
> >listObj<com.synopsys.iims.be.storage.Ifnet> with 6 entries
> >
> >20130107T172303 INFO c.c.a.d.MyDriver - Set time_stamp
> >integer via setTimeStamp to 1357513251
> >
> >
> >When I dump the records I see an array of 6 entries but the values all
> >reflect the last last entry in my java.util.List.
> >The print statements suggest I'm passing a list of 6 items with different
> >values,
> >
> > [amiller@localhost $] hadoop fs -copyToLocal /data/test_2013-01-07.avro
> > [amiller@localhost $] avro cat --fields=time_stamp,ifnet
> >test_2013-01-07.avro|less
> > {"time_stamp": 1357513251, "ifnet": [{"send_bps": 0, "recv_bps": 0,
> >"name": "losk"}, {"send_bps": 0, "recv_bps": 0, "name": "losk"},
> >{"send_bps": 0, "recv_bps": 0, "name": "losk"}, {"send_bps": 0,
> >"recv_bps": 0, "name": "losk"}, {"send_bps": 0, "recv_bps":
> > 0, "name": "losk"}, {"send_bps": 0, "recv_bps": 0, "name": "losk"}]}
> >
> > {"time_stamp": 1357513550, "ifnet": [{"send_bps": 0, "recv_bps": 0,
> >"name": "losk"}, {"send_bps": 0, "recv_bps": 0, "name": "losk"},
> >{"send_bps": 0, "recv_bps": 0, "name": "losk"}, {"send_bps": 0,
> >"recv_bps": 0, "name": "losk"}, {"send_bps": 0, "recv_bps":
> > 0, "name": "losk"}, {"send_bps": 0, "recv_bps": 0, "name": "losk"}]}
> >
> >
> >
> >Any ideas.
> >
>
> What API are you using? Generic, Specific, or Reflect? I am suspicious
> of the reflection, does it work when you bind it to one specific type? I
> sus=
> pect you could use generics to avoid the reflection but I have seen
> similar tasks get a little ugly.
>
> This is something you should be able to step through in a debugger; when
> you append the datum to the file, you can check the state of the object
> being written and that it has all of the expected data, then step through
> the code in the DatumWriter (if you use an IDE and maven, it should be
> trivial to attach the Avro source to your debugger) and see what it does
> with your list.
>
>
>
>
> >
> >
> >
> >
> >Alan
>
>
>
Re: issue with writing an array of records
Posted by Scott Carey <sc...@apache.org>.
On 1/7/13 8:35 AM, "Alan Miller" <al...@gmail.com> wrote:
>Hi, I have a schema with an array of records (I'm open to other
>suggestions too) field
>called ifnet to store misc attribute name/values for a host's network
>interfaces.
>e.g.
>
>
>{ "type": "record",
> "namespace": "com.company.avro.data",
> "name": "MyRecord",
> "doc": "My Data Record.",
> "fields": [
> // (required) fields
> {"name": "time_stamp", "type": "long"
> },
> {"name": "hostname", "type": "string"
> },
>
> // (optional) array of ifnet instances
> {"name": "ifnet",
> "type": ["null", {
> "type": "array",
> "items": { "type": "record", "name": "Ifnet",
> "namespace": "com.company.avro.data",
> "fields": [ {"name": "name", "type":
>"string"},
> {"name": "send_bps", "type":
>"long" },
> {"name": "recv_bps", "type":
>"long" }
> ]
> }
> }
> ]
> }
>
> ]
>}
First thought: Why the union of null and the array? It may be easier to
simply have an empty list when there are no Ifnet data.
>
>
>I can write the records, (time_stamp and hostname are correct) but
>my "array of records" field (ifnet) only contains the last element of my
>java List.
>
>Am I writing the field correctly? I'm trying to write the ifnet field
>with a
>java.util.List<com.company.avro.data.Ifnet>
>
>Here's the related code lines that write the ifnet field. (Yes, I'm
>attempting to use reflection
>because Ifnet is only 1 of approx 11 other array of record fields I'm
>trying to implement.)
>
> Class[] paramObj = new Class[1];
> paramObj[0] = Ifnet.class;
> Method method = cls.getMethod(methodName, List.class);
> jsonObj = new Ifnet();
> listOfObj = new ArrayList<Ifnet>();
> .......
>
>
> // in a loop building the List<Ifnet>.......
>
> LOG.info(String.format(" [%s] %s %s(%s) as %s", name,
>k,methNm,v,types[j].toString()));
> .......
>
> LOG.info(String.format(" [%s] setting name to %s", name, name));
>
> .......
>
> istOfObj.add(jsonObj);
>
> .......
>
> // then finally I call invoke with a List of Ifnet records
>
> if (method != null) { method.invoke(obj, listOfObj); }
> LOG.info(String.format(" invoking %s.%s",
>method.getClass().getSimpleName(), method.getName()));
> LOG.info(String.format(" param: listObj<%s> with %d entries" ,
>jsonObj.getClass().getName(), listOfObj.size()));
>
>
>and the respective output
>20130107T172303 INFO c.c.a.d.MyDriver - Set ifnet
>json via setIfnet(Ifnet object)
>20130107T172303 INFO c.c.a.d.MyDriver - [e0c] setting name to e0c
>20130107T172303 INFO c.c.a.d.MyDriver - [e0c] send_bps setSendBps(0)
>as class java.lang.Long
>20130107T172303 INFO c.c.a.d.MyDriver - [e0c] setting name to e0c
>20130107T172303 INFO c.c.a.d.MyDriver - [e0c] recv_bps setRecvBps(0)
>as class java.lang.Long
>20130107T172303 INFO c.c.a.d.MyDriver - [e0d] setting name to e0d
>20130107T172303 INFO c.c.a.d.MyDriver - [e0d] send_bps setSendBps(0)
>as class java.lang.Long
>20130107T172303 INFO c.c.a.d.MyDriver - [e0d] setting name to e0d
>20130107T172303 INFO c.c.a.d.MyDriver - [e0d] recv_bps setRecvBps(0)
>as class java.lang.Long
>20130107T172303 INFO c.c.a.d.MyDriver - [e0a] setting name to e0a
>20130107T172303 INFO c.c.a.d.MyDriver - [e0a] send_bps
>setSendBps(170720) as class java.lang.Long
>20130107T172303 INFO c.c.a.d.MyDriver - [e0a] setting name to e0a
>20130107T172303 INFO c.c.a.d.MyDriver - [e0a] recv_bps
>setRecvBps(244480) as class java.lang.Long
>20130107T172303 INFO c.c.a.d.MyDriver - [e0b] setting name to e0b
>20130107T172303 INFO c.c.a.d.MyDriver - [e0b] send_bps setSendBps(0)
>as class java.lang.Long
>20130107T172303 INFO c.c.a.d.MyDriver - [e0b] setting name to e0b
>20130107T172303 INFO c.c.a.d.MyDriver - [e0b] recv_bps setRecvBps(0)
>as class java.lang.Long
>20130107T172303 INFO c.c.a.d.MyDriver - [e0P] setting name to e0P
>20130107T172303 INFO c.c.a.d.MyDriver - [e0P] send_bps setSendBps(0)
>as class java.lang.Long
>20130107T172303 INFO c.c.a.d.MyDriver - [e0P] setting name to e0P
>20130107T172303 INFO c.c.a.d.MyDriver - [e0P] recv_bps setRecvBps(0)
>as class java.lang.Long
>20130107T172303 INFO c.c.a.d.MyDriver - [losk] setting name to losk
>20130107T172303 INFO c.c.a.d.MyDriver - [losk] send_bps setSendBps(0)
>as class java.lang.Long
>20130107T172303 INFO c.c.a.d.MyDriver - [losk] setting name to losk
>20130107T172303 INFO c.c.a.d.MyDriver - [losk] recv_bps setRecvBps(0)
>as class java.lang.Long
>20130107T172303 INFO c.c.a.d.MyDriver - invoking Method.setIfnet
>20130107T172303 INFO c.c.a.d.MyDriver - param:
>listObj<com.synopsys.iims.be.storage.Ifnet> with 6 entries
>
>20130107T172303 INFO c.c.a.d.MyDriver - Set time_stamp
>integer via setTimeStamp to 1357513251
>
>
>When I dump the records I see an array of 6 entries but the values all
>reflect the last last entry in my java.util.List.
>The print statements suggest I'm passing a list of 6 items with different
>values,
>
> [amiller@localhost $] hadoop fs -copyToLocal /data/test_2013-01-07.avro
> [amiller@localhost $] avro cat --fields=time_stamp,ifnet
>test_2013-01-07.avro|less
> {"time_stamp": 1357513251, "ifnet": [{"send_bps": 0, "recv_bps": 0,
>"name": "losk"}, {"send_bps": 0, "recv_bps": 0, "name": "losk"},
>{"send_bps": 0, "recv_bps": 0, "name": "losk"}, {"send_bps": 0,
>"recv_bps": 0, "name": "losk"}, {"send_bps": 0, "recv_bps":
> 0, "name": "losk"}, {"send_bps": 0, "recv_bps": 0, "name": "losk"}]}
>
> {"time_stamp": 1357513550, "ifnet": [{"send_bps": 0, "recv_bps": 0,
>"name": "losk"}, {"send_bps": 0, "recv_bps": 0, "name": "losk"},
>{"send_bps": 0, "recv_bps": 0, "name": "losk"}, {"send_bps": 0,
>"recv_bps": 0, "name": "losk"}, {"send_bps": 0, "recv_bps":
> 0, "name": "losk"}, {"send_bps": 0, "recv_bps": 0, "name": "losk"}]}
>
>
>
>Any ideas.
>
What API are you using? Generic, Specific, or Reflect? I am suspicious
of the reflection, does it work when you bind it to one specific type? I
sus=
pect you could use generics to avoid the reflection but I have seen
similar tasks get a little ugly.
This is something you should be able to step through in a debugger; when
you append the datum to the file, you can check the state of the object
being written and that it has all of the expected data, then step through
the code in the DatumWriter (if you use an IDE and maven, it should be
trivial to attach the Avro source to your debugger) and see what it does
with your list.
>
>
>
>
>Alan