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From Stephan Ewen <se...@apache.org>
Subject Re: NotSerializableException
Date Thu, 09 Jun 2016 18:38:04 GMT
You can also make the KeySelector a static inner class. That should work as
well.

On Thu, Jun 9, 2016 at 7:00 PM, Tarandeep Singh <tarandeep@gmail.com> wrote:

> Thank you Aljoscha and Fabian for your replies.
>
> @Aljoscha: when you said "cleaner is not used in CoGroup.where(). I'm
> afraid this is a bug", I am assuming you are referring to Flink engine
> itself.
>
> @Fabian: thanks for the optimization tip.
>
> This is how I have got it working (with a hack): In my dataset, the join
> field/key can be null otherwise .where(fieldName) works and I don't get
> not-serializable exception. So I applied a MapFunction to DataSet and put a
> dummy value in the join field/key where it was null. Then In the join
> function, I change it back to null.
>
> Best,
> Tarandeep
>
> On Thu, Jun 9, 2016 at 7:06 AM, Aljoscha Krettek <aljoscha@apache.org>
> wrote:
>
>> Hi,
>> the problem is that the KeySelector is an anonymous inner class and as
>> such as a reference to the outer RecordFilterer object. Normally, this
>> would be rectified by the closure cleaner but the cleaner is not used in
>> CoGroup.where(). I'm afraid this is a bug.
>>
>> Best,
>> Aljoscha
>>
>>
>> On Thu, 9 Jun 2016 at 14:06 Fabian Hueske <fhueske@gmail.com> wrote:
>>
>>> Hi Tarandeep,
>>>
>>> the exception suggests that Flink tries to serialize RecordsFilterer as
>>> a user function (this happens via Java Serialization).
>>> I said suggests because the code that uses RecordsFilterer is not
>>> included.
>>>
>>> To me it looks like RecordsFilterer should not be used as a user
>>> function. It is a helper class to construct a DataSet program, so it should
>>> not be shipped for execution.
>>> You would use such a class as follows:
>>>
>>> DataSet<T> records = ...
>>> DataSet<String> filterIDs = ...
>>>
>>> RecordsFilterer rf = new RecordsFilterer();
>>> DataSet<Tuple2<Boolean, T>> result = rf.addFilterFlag(records,
>>> filterIDs, "myField");
>>>
>>> Regarding the join code, I would suggest an optimization.
>>> Instead of using CoGroup, I would use distinct and an OuterJoin like
>>> this:
>>>
>>> DataSet<String> distIds = filtereredIds.distinct();
>>> DataSet<Tuple2<Boolean, T> result = records
>>>   .leftOuterJoin(distIds)
>>>   .where(KEYSELECTOR)
>>>   .equalTo("*") // use full string as key
>>>   .with(JOINFUNC) // set Bool to false if right == null, true otherwise
>>>
>>> Best, Fabian
>>>
>>> 2016-06-09 2:28 GMT+02:00 Tarandeep Singh <tarandeep@gmail.com>:
>>>
>>>> Hi,
>>>>
>>>> I am getting NoSerializableException in this class-
>>>>
>>>> 
>>>>
>>>> public class RecordsFilterer<T extends GenericRecord> {
>>>>
>>>>     public DataSet<Tuple2<Boolean,T>> addFilterFlag(DataSet<T>
dataset, DataSet<String> filteredIds, String fieldName) {
>>>>         return dataset.coGroup(filteredIds)
>>>>                 .where(new KeySelector<T, String>() {
>>>>                     @Override
>>>>                     public String getKey(T t) throws Exception {
>>>>                         String s = (String) t.get(fieldName);
>>>>                         return s != null ? s : UUID.randomUUID().toString();
>>>>                     }
>>>>                 })
>>>>                 .equalTo((KeySelector<String, String>) s -> s)
>>>>                 .with(new CoGroupFunction<T, String, Tuple2<Boolean,T>>()
{
>>>>                     @Override
>>>>                     public void coGroup(Iterable<T> records, Iterable<String>
ids,
>>>>                                         Collector<Tuple2<Boolean,T>>
collector) throws Exception {
>>>>                         boolean filterFlag = false;
>>>>                         for (String id : ids) {
>>>>                             filterFlag = true;
>>>>                         }
>>>>
>>>>                         for (T record : records) {
>>>>                             collector.collect(new Tuple2<>(filterFlag,
record));
>>>>                         }
>>>>                     }
>>>>                 });
>>>>
>>>>     }
>>>> }
>>>>
>>>>
>>>> What I am trying to do is write a generic code that will join Avro
>>>> records (of different types) with String records and there is a match add
a
>>>> filter flag. This way I can use the same code for different Avro record
>>>> types. But I am getting this exception-
>>>>
>>>> Exception in thread "main"
>>>> org.apache.flink.optimizer.CompilerException: Error translating node 'Map
>>>> "Key Extractor" : MAP [[ GlobalProperties [partitioning=RANDOM_PARTITIONED]
>>>> ]] [[ LocalProperties [ordering=null, grouped=null, unique=null] ]]': Could
>>>> not write the user code wrapper class
>>>> org.apache.flink.api.common.operators.util.UserCodeObjectWrapper :
>>>> java.io.NotSerializableException:
>>>> com.styleseat.dataplatform.etl.jobs.boundary.RecordsFilterer
>>>>     at
>>>> org.apache.flink.optimizer.plantranslate.JobGraphGenerator.preVisit(JobGraphGenerator.java:386)
>>>>     at
>>>> org.apache.flink.optimizer.plantranslate.JobGraphGenerator.preVisit(JobGraphGenerator.java:109)
>>>>     at
>>>> org.apache.flink.optimizer.plan.SingleInputPlanNode.accept(SingleInputPlanNode.java:198)
>>>>     at
>>>> org.apache.flink.optimizer.plan.DualInputPlanNode.accept(DualInputPlanNode.java:163)
>>>>     at
>>>> org.apache.flink.optimizer.plan.SingleInputPlanNode.accept(SingleInputPlanNode.java:199)
>>>>     at
>>>> org.apache.flink.optimizer.plan.SingleInputPlanNode.accept(SingleInputPlanNode.java:199)
>>>>     at
>>>> org.apache.flink.optimizer.plan.OptimizedPlan.accept(OptimizedPlan.java:128)
>>>>     at
>>>> org.apache.flink.optimizer.plantranslate.JobGraphGenerator.compileJobGraph(JobGraphGenerator.java:188)
>>>>     at
>>>> org.apache.flink.client.LocalExecutor.executePlan(LocalExecutor.java:187)
>>>>     at
>>>> org.apache.flink.api.java.LocalEnvironment.execute(LocalEnvironment.java:90)
>>>>     at
>>>> org.apache.flink.api.java.ExecutionEnvironment.execute(ExecutionEnvironment.java:855)
>>>>     at
>>>> com.styleseat.dataplatform.etl.jobs.search.RunSearchLogProcessorV2.runSearchLogProcessor(RunSearchLogProcessorV2.java:57)
>>>>     at
>>>> com.styleseat.dataplatform.etl.jobs.search.RunSearchLogProcessorV2.main(RunSearchLogProcessorV2.java:32)
>>>>     at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
>>>>     at
>>>> sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
>>>>     at
>>>> sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
>>>>     at java.lang.reflect.Method.invoke(Method.java:497)
>>>>     at
>>>> com.intellij.rt.execution.application.AppMain.main(AppMain.java:144)
>>>> Caused by:
>>>> org.apache.flink.runtime.operators.util.CorruptConfigurationException:
>>>> Could not write the user code wrapper class
>>>> org.apache.flink.api.common.operators.util.UserCodeObjectWrapper :
>>>> java.io.NotSerializableException: RecordsFilterer
>>>>     at
>>>> org.apache.flink.runtime.operators.util.TaskConfig.setStubWrapper(TaskConfig.java:275)
>>>>     at
>>>> org.apache.flink.optimizer.plantranslate.JobGraphGenerator.createSingleInputVertex(JobGraphGenerator.java:843)
>>>>     at
>>>> org.apache.flink.optimizer.plantranslate.JobGraphGenerator.preVisit(JobGraphGenerator.java:331)
>>>>     ... 17 more
>>>> Caused by: java.io.NotSerializableException: RecordsFilterer
>>>>     at
>>>> java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1184)
>>>>     at
>>>> java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1548)
>>>>     at
>>>> java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1509)
>>>>     at
>>>> java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1432)
>>>>     at
>>>> java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
>>>>     at
>>>> java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1548)
>>>>     at
>>>> java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1509)
>>>>     at
>>>> java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1432)
>>>>     at
>>>> java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
>>>>     at
>>>> java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1548)
>>>>     at
>>>> java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1509)
>>>>     at
>>>> java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1432)
>>>>     at
>>>> java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
>>>>     at
>>>> java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:348)
>>>>     at
>>>> org.apache.flink.util.InstantiationUtil.serializeObject(InstantiationUtil.java:300)
>>>>     at
>>>> org.apache.flink.util.InstantiationUtil.writeObjectToConfig(InstantiationUtil.java:252)
>>>>     at
>>>> org.apache.flink.runtime.operators.util.TaskConfig.setStubWrapper(TaskConfig.java:273)
>>>>     ... 19 more
>>>>
>>>>
>>>> Please help me understand why I get this exception and how to fix it
>>>> [rewrite code may be?]
>>>>
>>>> Thanks,
>>>> Tarandeep
>>>>
>>>>
>>>>
>>>
>

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