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Posted to users@apex.apache.org by Junguk Cho <jm...@gmail.com> on 2016/06/10 15:37:45 UTC
Dynamic Application Modification
Hi.
I explore "Dynamic Application Modification" with this example(
https://github.com/DataTorrent/examples/tree/master/tutorials/dynamic-partition
).
To be clear, basically, application developers carefully design a program.
For Dynamic Partitioning, in "dynamic partition" example, it uses
threadhold to adjust partition. In addition, to use Modification of DAG
structure, app developers should make program like java classes to use them
later.
Do I interpret that they are determined "compiling time"?
How do I use "Load balance and Sticky Key" in Apex?
I would like to create this topology for word counting.
For example,
B operator
A operator -> -> one onperator
C Operator
A sends the same values like "word" to the same operator ( B or C )?
Can we specify this rule in code and how to make two process for B and C
with one class?
Thanks,
Junguk
Re: Dynamic Application Modification
Posted by Sandesh Hegde <sa...@datatorrent.com>.
I will leave the 1st question to others to answer.
Answer to your second question is - It is a roadmap item, currently all the
operators needs to be present in the *.apa file.
On Fri, Jun 10, 2016 at 11:36 AM Junguk Cho <jm...@gmail.com> wrote:
> Hi, Ram.
>
> Thank you for reply.
> I have following question.
>
> 1. Where do we specify policy to use "Load balance" or "Sticky Key"?
>
> 2. This is just general question.
> For example, I would like to run A class now as one operator and then
> later I need other tasks which I do not think.
> At that time, could I load this new class in current DAG even though it is
> not included in *.apa file.
>
>
> Thanks,
> Junguk
>
>
> 2016-06-10 12:03 GMT-04:00 Munagala Ramanath <ra...@datatorrent.com>:
>
>> You don't need dynamic partitioning to achieve that topology. You can
>> simply create your DAG as: A --> X --> Y and then set the *PARTITIONER*
>> attribute on X
>> as discussed in the "Advanced Features" section of the TopN words
>> tutorial at:
>> http://docs.datatorrent.com/tutorials/topnwords-c7/
>>
>> The stanza in your properties file should look something like this (with
>> suitable changes
>> for the application and operator names):
>>
>> *<property>*
>> *
>> <name>dt.application.TopNWordsWithQueries.operator.wordReader.attr.PARTITIONER</name>*
>> *
>> <value>com.datatorrent.common.partitioner.StatelessPartitioner:2</value>*
>> *</property>*
>>
>> The platform will then create two replicas of X.
>>
>> For the rest, could you provide additional details of what you are trying
>> to accomplish, what
>> you tried and what sort of problems you encountered ? That will help us
>> provide more precise answers.
>>
>> Ram
>>
>> On Fri, Jun 10, 2016 at 8:37 AM, Junguk Cho <jm...@gmail.com> wrote:
>>
>>> Hi.
>>>
>>> I explore "Dynamic Application Modification" with this example(
>>> https://github.com/DataTorrent/examples/tree/master/tutorials/dynamic-partition
>>> ).
>>>
>>>
>>> To be clear, basically, application developers carefully design a
>>> program.
>>> For Dynamic Partitioning, in "dynamic partition" example, it uses
>>> threadhold to adjust partition. In addition, to use Modification of DAG
>>> structure, app developers should make program like java classes to use them
>>> later.
>>> Do I interpret that they are determined "compiling time"?
>>>
>>> How do I use "Load balance and Sticky Key" in Apex?
>>> I would like to create this topology for word counting.
>>> For example,
>>> B operator
>>> A operator -> -> one
>>> onperator
>>> C Operator
>>>
>>> A sends the same values like "word" to the same operator ( B or C )?
>>> Can we specify this rule in code and how to make two process for B and C
>>> with one class?
>>>
>>> Thanks,
>>> Junguk
>>>
>>
>>
>
Re: Dynamic Application Modification
Posted by Ashwin Chandra Putta <as...@gmail.com>.
Hi,
You can create your stream codec to define custom routing. Default is
sticky key partitioning.
See this example Codec3.java here:
https://github.com/DataTorrent/examples/tree/master/tutorials/partition/src/main/java/com/example/myapexapp
For load balancing, the getPartition method can keep returning incremental
value for every call for partition. So, it will become round robin instead
of sticky key. In case of sticky key, it returns the hashCode of the object.
More documentation here:
https://apex.apache.org/docs/apex/application_development/#partitioning
Regards,
Ashwin.
On Fri, Jun 10, 2016 at 2:39 PM, Junguk Cho <jm...@gmail.com> wrote:
> Hi.
>
> Thank you for replies.
>
> In Storm, storm APIs provides several grouping methods(
> http://storm.apache.org/releases/current/Concepts.html).
> For example, app developers specify the number of replica and routing
> rules like shuffleGrouping and fieldsGrouping.
>
> builder.setSpout("spout", new RandomSentenceSpout(), 5);
> builder.setBolt("split", new SplitSentence(), 8).shuffleGrouping("spout");
> builder.setBolt("count", new WordCount(), 12).fieldsGrouping("split", new
> Fields("word"));
>
> In apex, we can set the number of replica in property files and for
> partitions except for "sticky" we can use "Partition" and StreamCodec.
>
> Is my understanding correct? Thanks in advance. Junguk
>
>
>
>
> 2016-06-10 16:16 GMT-04:00 Munagala Ramanath <ra...@datatorrent.com>:
>
>> There is no mechanism for automatic load balancing across the board; some
>> individual operators
>> support it (e.g. Kafka input operator) out of the box. You can implement
>> it in your own operator by using a
>> custom partitioner.
>>
>> Keys are sticky by default since the hashcode is used to distribute
>> tuples to partitions. There is
>> no special setting for this. You can gain more control over how the
>> distribution happens by
>> using a StreamCodec.
>>
>> Ram
>>
>> On Fri, Jun 10, 2016 at 11:36 AM, Junguk Cho <jm...@gmail.com> wrote:
>>
>>> Hi, Ram.
>>>
>>> Thank you for reply.
>>> I have following question.
>>>
>>> 1. Where do we specify policy to use "Load balance" or "Sticky Key"?
>>>
>>> 2. This is just general question.
>>> For example, I would like to run A class now as one operator and then
>>> later I need other tasks which I do not think.
>>> At that time, could I load this new class in current DAG even though it
>>> is not included in *.apa file.
>>>
>>>
>>> Thanks,
>>> Junguk
>>>
>>>
>>> 2016-06-10 12:03 GMT-04:00 Munagala Ramanath <ra...@datatorrent.com>:
>>>
>>>> You don't need dynamic partitioning to achieve that topology. You can
>>>> simply create your DAG as: A --> X --> Y and then set the *PARTITIONER*
>>>> attribute on X
>>>> as discussed in the "Advanced Features" section of the TopN words
>>>> tutorial at:
>>>> http://docs.datatorrent.com/tutorials/topnwords-c7/
>>>>
>>>> The stanza in your properties file should look something like this
>>>> (with suitable changes
>>>> for the application and operator names):
>>>>
>>>> *<property>*
>>>> *
>>>> <name>dt.application.TopNWordsWithQueries.operator.wordReader.attr.PARTITIONER</name>*
>>>> *
>>>> <value>com.datatorrent.common.partitioner.StatelessPartitioner:2</value>*
>>>> *</property>*
>>>>
>>>> The platform will then create two replicas of X.
>>>>
>>>> For the rest, could you provide additional details of what you are
>>>> trying to accomplish, what
>>>> you tried and what sort of problems you encountered ? That will help us
>>>> provide more precise answers.
>>>>
>>>> Ram
>>>>
>>>> On Fri, Jun 10, 2016 at 8:37 AM, Junguk Cho <jm...@gmail.com> wrote:
>>>>
>>>>> Hi.
>>>>>
>>>>> I explore "Dynamic Application Modification" with this example(
>>>>> https://github.com/DataTorrent/examples/tree/master/tutorials/dynamic-partition
>>>>> ).
>>>>>
>>>>>
>>>>> To be clear, basically, application developers carefully design a
>>>>> program.
>>>>> For Dynamic Partitioning, in "dynamic partition" example, it uses
>>>>> threadhold to adjust partition. In addition, to use Modification of DAG
>>>>> structure, app developers should make program like java classes to use them
>>>>> later.
>>>>> Do I interpret that they are determined "compiling time"?
>>>>>
>>>>> How do I use "Load balance and Sticky Key" in Apex?
>>>>> I would like to create this topology for word counting.
>>>>> For example,
>>>>> B operator
>>>>> A operator -> -> one
>>>>> onperator
>>>>> C Operator
>>>>>
>>>>> A sends the same values like "word" to the same operator ( B or C )?
>>>>> Can we specify this rule in code and how to make two process for B and
>>>>> C with one class?
>>>>>
>>>>> Thanks,
>>>>> Junguk
>>>>>
>>>>
>>>>
>>>
>>
>
--
Regards,
Ashwin.
Re: Dynamic Application Modification
Posted by Sandesh Hegde <sa...@datatorrent.com>.
You can set the platform Attributes & operators properties either from the
property file or from the application. ( dag.setAttribute..,
dag.setInputPortAttribute, dag.setOutputPortAttribute )
StreamCodec can be used to - Route the tuples flowing through the streams
and also to change the serializer used for the tuples, ( default is Kryo )
On Fri, Jun 10, 2016 at 2:40 PM Junguk Cho <jm...@gmail.com> wrote:
> Hi.
>
> Thank you for replies.
>
> In Storm, storm APIs provides several grouping methods(
> http://storm.apache.org/releases/current/Concepts.html).
> For example, app developers specify the number of replica and routing
> rules like shuffleGrouping and fieldsGrouping.
>
> builder.setSpout("spout", new RandomSentenceSpout(), 5);
> builder.setBolt("split", new SplitSentence(), 8).shuffleGrouping("spout");
> builder.setBolt("count", new WordCount(), 12).fieldsGrouping("split", new
> Fields("word"));
>
> In apex, we can set the number of replica in property files and for
> partitions except for "sticky" we can use "Partition" and StreamCodec.
>
> Is my understanding correct? Thanks in advance. Junguk
>
>
>
>
> 2016-06-10 16:16 GMT-04:00 Munagala Ramanath <ra...@datatorrent.com>:
>
>> There is no mechanism for automatic load balancing across the board; some
>> individual operators
>> support it (e.g. Kafka input operator) out of the box. You can implement
>> it in your own operator by using a
>> custom partitioner.
>>
>> Keys are sticky by default since the hashcode is used to distribute
>> tuples to partitions. There is
>> no special setting for this. You can gain more control over how the
>> distribution happens by
>> using a StreamCodec.
>>
>> Ram
>>
>> On Fri, Jun 10, 2016 at 11:36 AM, Junguk Cho <jm...@gmail.com> wrote:
>>
>>> Hi, Ram.
>>>
>>> Thank you for reply.
>>> I have following question.
>>>
>>> 1. Where do we specify policy to use "Load balance" or "Sticky Key"?
>>>
>>> 2. This is just general question.
>>> For example, I would like to run A class now as one operator and then
>>> later I need other tasks which I do not think.
>>> At that time, could I load this new class in current DAG even though it
>>> is not included in *.apa file.
>>>
>>>
>>> Thanks,
>>> Junguk
>>>
>>>
>>> 2016-06-10 12:03 GMT-04:00 Munagala Ramanath <ra...@datatorrent.com>:
>>>
>>>> You don't need dynamic partitioning to achieve that topology. You can
>>>> simply create your DAG as: A --> X --> Y and then set the *PARTITIONER*
>>>> attribute on X
>>>> as discussed in the "Advanced Features" section of the TopN words
>>>> tutorial at:
>>>> http://docs.datatorrent.com/tutorials/topnwords-c7/
>>>>
>>>> The stanza in your properties file should look something like this
>>>> (with suitable changes
>>>> for the application and operator names):
>>>>
>>>> *<property>*
>>>> *
>>>> <name>dt.application.TopNWordsWithQueries.operator.wordReader.attr.PARTITIONER</name>*
>>>> *
>>>> <value>com.datatorrent.common.partitioner.StatelessPartitioner:2</value>*
>>>> *</property>*
>>>>
>>>> The platform will then create two replicas of X.
>>>>
>>>> For the rest, could you provide additional details of what you are
>>>> trying to accomplish, what
>>>> you tried and what sort of problems you encountered ? That will help us
>>>> provide more precise answers.
>>>>
>>>> Ram
>>>>
>>>> On Fri, Jun 10, 2016 at 8:37 AM, Junguk Cho <jm...@gmail.com> wrote:
>>>>
>>>>> Hi.
>>>>>
>>>>> I explore "Dynamic Application Modification" with this example(
>>>>> https://github.com/DataTorrent/examples/tree/master/tutorials/dynamic-partition
>>>>> ).
>>>>>
>>>>>
>>>>> To be clear, basically, application developers carefully design a
>>>>> program.
>>>>> For Dynamic Partitioning, in "dynamic partition" example, it uses
>>>>> threadhold to adjust partition. In addition, to use Modification of DAG
>>>>> structure, app developers should make program like java classes to use them
>>>>> later.
>>>>> Do I interpret that they are determined "compiling time"?
>>>>>
>>>>> How do I use "Load balance and Sticky Key" in Apex?
>>>>> I would like to create this topology for word counting.
>>>>> For example,
>>>>> B operator
>>>>> A operator -> -> one
>>>>> onperator
>>>>> C Operator
>>>>>
>>>>> A sends the same values like "word" to the same operator ( B or C )?
>>>>> Can we specify this rule in code and how to make two process for B and
>>>>> C with one class?
>>>>>
>>>>> Thanks,
>>>>> Junguk
>>>>>
>>>>
>>>>
>>>
>>
>
Re: Dynamic Application Modification
Posted by Junguk Cho <jm...@gmail.com>.
Hi.
Thank you for replies.
In Storm, storm APIs provides several grouping methods(
http://storm.apache.org/releases/current/Concepts.html).
For example, app developers specify the number of replica and routing rules
like shuffleGrouping and fieldsGrouping.
builder.setSpout("spout", new RandomSentenceSpout(), 5);
builder.setBolt("split", new SplitSentence(), 8).shuffleGrouping("spout");
builder.setBolt("count", new WordCount(), 12).fieldsGrouping("split", new
Fields("word"));
In apex, we can set the number of replica in property files and for
partitions except for "sticky" we can use "Partition" and StreamCodec.
Is my understanding correct? Thanks in advance. Junguk
2016-06-10 16:16 GMT-04:00 Munagala Ramanath <ra...@datatorrent.com>:
> There is no mechanism for automatic load balancing across the board; some
> individual operators
> support it (e.g. Kafka input operator) out of the box. You can implement
> it in your own operator by using a
> custom partitioner.
>
> Keys are sticky by default since the hashcode is used to distribute tuples
> to partitions. There is
> no special setting for this. You can gain more control over how the
> distribution happens by
> using a StreamCodec.
>
> Ram
>
> On Fri, Jun 10, 2016 at 11:36 AM, Junguk Cho <jm...@gmail.com> wrote:
>
>> Hi, Ram.
>>
>> Thank you for reply.
>> I have following question.
>>
>> 1. Where do we specify policy to use "Load balance" or "Sticky Key"?
>>
>> 2. This is just general question.
>> For example, I would like to run A class now as one operator and then
>> later I need other tasks which I do not think.
>> At that time, could I load this new class in current DAG even though it
>> is not included in *.apa file.
>>
>>
>> Thanks,
>> Junguk
>>
>>
>> 2016-06-10 12:03 GMT-04:00 Munagala Ramanath <ra...@datatorrent.com>:
>>
>>> You don't need dynamic partitioning to achieve that topology. You can
>>> simply create your DAG as: A --> X --> Y and then set the *PARTITIONER*
>>> attribute on X
>>> as discussed in the "Advanced Features" section of the TopN words
>>> tutorial at:
>>> http://docs.datatorrent.com/tutorials/topnwords-c7/
>>>
>>> The stanza in your properties file should look something like this (with
>>> suitable changes
>>> for the application and operator names):
>>>
>>> *<property>*
>>> *
>>> <name>dt.application.TopNWordsWithQueries.operator.wordReader.attr.PARTITIONER</name>*
>>> *
>>> <value>com.datatorrent.common.partitioner.StatelessPartitioner:2</value>*
>>> *</property>*
>>>
>>> The platform will then create two replicas of X.
>>>
>>> For the rest, could you provide additional details of what you are
>>> trying to accomplish, what
>>> you tried and what sort of problems you encountered ? That will help us
>>> provide more precise answers.
>>>
>>> Ram
>>>
>>> On Fri, Jun 10, 2016 at 8:37 AM, Junguk Cho <jm...@gmail.com> wrote:
>>>
>>>> Hi.
>>>>
>>>> I explore "Dynamic Application Modification" with this example(
>>>> https://github.com/DataTorrent/examples/tree/master/tutorials/dynamic-partition
>>>> ).
>>>>
>>>>
>>>> To be clear, basically, application developers carefully design a
>>>> program.
>>>> For Dynamic Partitioning, in "dynamic partition" example, it uses
>>>> threadhold to adjust partition. In addition, to use Modification of DAG
>>>> structure, app developers should make program like java classes to use them
>>>> later.
>>>> Do I interpret that they are determined "compiling time"?
>>>>
>>>> How do I use "Load balance and Sticky Key" in Apex?
>>>> I would like to create this topology for word counting.
>>>> For example,
>>>> B operator
>>>> A operator -> -> one
>>>> onperator
>>>> C Operator
>>>>
>>>> A sends the same values like "word" to the same operator ( B or C )?
>>>> Can we specify this rule in code and how to make two process for B and
>>>> C with one class?
>>>>
>>>> Thanks,
>>>> Junguk
>>>>
>>>
>>>
>>
>
Re: Dynamic Application Modification
Posted by Munagala Ramanath <ra...@datatorrent.com>.
There is no mechanism for automatic load balancing across the board; some
individual operators
support it (e.g. Kafka input operator) out of the box. You can implement it
in your own operator by using a
custom partitioner.
Keys are sticky by default since the hashcode is used to distribute tuples
to partitions. There is
no special setting for this. You can gain more control over how the
distribution happens by
using a StreamCodec.
Ram
On Fri, Jun 10, 2016 at 11:36 AM, Junguk Cho <jm...@gmail.com> wrote:
> Hi, Ram.
>
> Thank you for reply.
> I have following question.
>
> 1. Where do we specify policy to use "Load balance" or "Sticky Key"?
>
> 2. This is just general question.
> For example, I would like to run A class now as one operator and then
> later I need other tasks which I do not think.
> At that time, could I load this new class in current DAG even though it is
> not included in *.apa file.
>
>
> Thanks,
> Junguk
>
>
> 2016-06-10 12:03 GMT-04:00 Munagala Ramanath <ra...@datatorrent.com>:
>
>> You don't need dynamic partitioning to achieve that topology. You can
>> simply create your DAG as: A --> X --> Y and then set the *PARTITIONER*
>> attribute on X
>> as discussed in the "Advanced Features" section of the TopN words
>> tutorial at:
>> http://docs.datatorrent.com/tutorials/topnwords-c7/
>>
>> The stanza in your properties file should look something like this (with
>> suitable changes
>> for the application and operator names):
>>
>> *<property>*
>> *
>> <name>dt.application.TopNWordsWithQueries.operator.wordReader.attr.PARTITIONER</name>*
>> *
>> <value>com.datatorrent.common.partitioner.StatelessPartitioner:2</value>*
>> *</property>*
>>
>> The platform will then create two replicas of X.
>>
>> For the rest, could you provide additional details of what you are trying
>> to accomplish, what
>> you tried and what sort of problems you encountered ? That will help us
>> provide more precise answers.
>>
>> Ram
>>
>> On Fri, Jun 10, 2016 at 8:37 AM, Junguk Cho <jm...@gmail.com> wrote:
>>
>>> Hi.
>>>
>>> I explore "Dynamic Application Modification" with this example(
>>> https://github.com/DataTorrent/examples/tree/master/tutorials/dynamic-partition
>>> ).
>>>
>>>
>>> To be clear, basically, application developers carefully design a
>>> program.
>>> For Dynamic Partitioning, in "dynamic partition" example, it uses
>>> threadhold to adjust partition. In addition, to use Modification of DAG
>>> structure, app developers should make program like java classes to use them
>>> later.
>>> Do I interpret that they are determined "compiling time"?
>>>
>>> How do I use "Load balance and Sticky Key" in Apex?
>>> I would like to create this topology for word counting.
>>> For example,
>>> B operator
>>> A operator -> -> one
>>> onperator
>>> C Operator
>>>
>>> A sends the same values like "word" to the same operator ( B or C )?
>>> Can we specify this rule in code and how to make two process for B and C
>>> with one class?
>>>
>>> Thanks,
>>> Junguk
>>>
>>
>>
>
Re: Dynamic Application Modification
Posted by Junguk Cho <jm...@gmail.com>.
Hi, Ram.
Thank you for reply.
I have following question.
1. Where do we specify policy to use "Load balance" or "Sticky Key"?
2. This is just general question.
For example, I would like to run A class now as one operator and then later
I need other tasks which I do not think.
At that time, could I load this new class in current DAG even though it is
not included in *.apa file.
Thanks,
Junguk
2016-06-10 12:03 GMT-04:00 Munagala Ramanath <ra...@datatorrent.com>:
> You don't need dynamic partitioning to achieve that topology. You can
> simply create your DAG as: A --> X --> Y and then set the *PARTITIONER*
> attribute on X
> as discussed in the "Advanced Features" section of the TopN words tutorial
> at:
> http://docs.datatorrent.com/tutorials/topnwords-c7/
>
> The stanza in your properties file should look something like this (with
> suitable changes
> for the application and operator names):
>
> *<property>*
> *
> <name>dt.application.TopNWordsWithQueries.operator.wordReader.attr.PARTITIONER</name>*
> *
> <value>com.datatorrent.common.partitioner.StatelessPartitioner:2</value>*
> *</property>*
>
> The platform will then create two replicas of X.
>
> For the rest, could you provide additional details of what you are trying
> to accomplish, what
> you tried and what sort of problems you encountered ? That will help us
> provide more precise answers.
>
> Ram
>
> On Fri, Jun 10, 2016 at 8:37 AM, Junguk Cho <jm...@gmail.com> wrote:
>
>> Hi.
>>
>> I explore "Dynamic Application Modification" with this example(
>> https://github.com/DataTorrent/examples/tree/master/tutorials/dynamic-partition
>> ).
>>
>>
>> To be clear, basically, application developers carefully design a program.
>> For Dynamic Partitioning, in "dynamic partition" example, it uses
>> threadhold to adjust partition. In addition, to use Modification of DAG
>> structure, app developers should make program like java classes to use them
>> later.
>> Do I interpret that they are determined "compiling time"?
>>
>> How do I use "Load balance and Sticky Key" in Apex?
>> I would like to create this topology for word counting.
>> For example,
>> B operator
>> A operator -> -> one
>> onperator
>> C Operator
>>
>> A sends the same values like "word" to the same operator ( B or C )?
>> Can we specify this rule in code and how to make two process for B and C
>> with one class?
>>
>> Thanks,
>> Junguk
>>
>
>
Re: Dynamic Application Modification
Posted by Munagala Ramanath <ra...@datatorrent.com>.
You don't need dynamic partitioning to achieve that topology. You can
simply create your DAG as: A --> X --> Y and then set the *PARTITIONER*
attribute on X
as discussed in the "Advanced Features" section of the TopN words tutorial
at:
http://docs.datatorrent.com/tutorials/topnwords-c7/
The stanza in your properties file should look something like this (with
suitable changes
for the application and operator names):
*<property>*
*
<name>dt.application.TopNWordsWithQueries.operator.wordReader.attr.PARTITIONER</name>*
* <value>com.datatorrent.common.partitioner.StatelessPartitioner:2</value>*
*</property>*
The platform will then create two replicas of X.
For the rest, could you provide additional details of what you are trying
to accomplish, what
you tried and what sort of problems you encountered ? That will help us
provide more precise answers.
Ram
On Fri, Jun 10, 2016 at 8:37 AM, Junguk Cho <jm...@gmail.com> wrote:
> Hi.
>
> I explore "Dynamic Application Modification" with this example(
> https://github.com/DataTorrent/examples/tree/master/tutorials/dynamic-partition
> ).
>
>
> To be clear, basically, application developers carefully design a program.
> For Dynamic Partitioning, in "dynamic partition" example, it uses
> threadhold to adjust partition. In addition, to use Modification of DAG
> structure, app developers should make program like java classes to use them
> later.
> Do I interpret that they are determined "compiling time"?
>
> How do I use "Load balance and Sticky Key" in Apex?
> I would like to create this topology for word counting.
> For example,
> B operator
> A operator -> -> one onperator
> C Operator
>
> A sends the same values like "word" to the same operator ( B or C )?
> Can we specify this rule in code and how to make two process for B and C
> with one class?
>
> Thanks,
> Junguk
>