Re: OptimizedClassDescriptor verifyChecksum object set as optional

[姜 为]

Hi Denis,

This is not what I want ,but it works for my service.
Thank you!

Jiang

> 在 2015年11月11日，下午9:00，Denis Magda  写道：
> 
> Hi Jiang,
> 
> I'm a bit confused why you can't give different names to the services located 
> in different modules. If each service has a different name then my approach 
> will work for you, doesn't it?
> 
>   But if my service is by ModuleA.ExampleServiceImpl call 
> ModuleB.ExampleServiceImpl,
>   and ModuleB.ExampleServiceImpl call other complicated service.
> 
> 
> Could you provide me with the code showing what you're trying to achieve.
> 
> BTW, you use service notion in the thread. Probably you can implement 
> everything using Ignite Services module:
> https://apacheignite.readme.io/docs/service-grid 
> 
> What do you think?
> 
> 
> Regards,
> Denis
> 
> On 11/11/2015 5:54 AM, 姜 为 wrote:
>> Hi Denis:
>> 
>>  I tried compute.call(new ExampleServiceImplA());
>> 
>>  But if my service is by ModuleA.ExampleServiceImpl call 
>> ModuleB.ExampleServiceImpl,
>>  and ModuleB.ExampleServiceImpl call other complicated service.
>>  
>>  The ModuleA only has ExampleServiceImpl there is none ModuleB.other 
>> service.
>>  It does not work.
>> 
>> 
>>> 在 2015年11月10日，下午9:55，Denis Magda >>  >> >> 写道：
>>> 
>>> It should fail because you send your service impl inside of Callable
>>> compute.call(new Callable(new ExampleServiceImplA()));
>>> 
>>> Callable is loaded by application class loader and presents on both the 
>>> sender and receiver. This leads to the situation when the receiver tries to 
>>> loads ExampleServiceImplA using the app class loader as well.
>>> 
>>> To avoid this try to implement IgniteCallable by ExampleServiceImplA and 
>>> send the task this way:
>>> 
>>> compute.call(new ExampleServiceImplA());
>>> 
>>> 
 I think. If I have lots of type servers. It will be ExampleServiceImpl1 2 
 3 4 5….,will look very bloated.
>>> You can use java 8 closures sending a particular one depending on a server 
>>> type. Will it work for you?
>>> https://apacheignite.readme.io/docs/distributed-closures 
>>>  
>>> >> >
>>> 
>>> 
>>> Regards,
>>> Denis
>>> On 11/10/2015 4:31 PM, 姜 为 wrote:
 Hi Denis,
 
I tried your suggested,  here is the code : 
 >https://github.com/wmz7year/ignite-test/commit/4eaa4231e165eaa4de00dab94cd394f629e68497
  
 
  
 >

But I still got ClassNotFoundException.
 
<邮件附件.png>
 
 
I think. If I have lots of type servers. It will be ExampleServiceImpl1 
 2 3 4 5….,will look very bloated.

 
> 在 2015年11月10日，下午8:02，Denis Magda <  >dma...@gridgain.com 
>  >> 写道：
> 
> Jiang,
> 
> This exception happens exactly because you have two implementations with 
> the same name. If the names were different you wouldn't get to the point 
> of checksum validation.
> Here I fully share Val's opinion that checksum's verification shouldn't 
> be optional and it's a responsibility of an application to take care of 
> such situations.
> 
> I see the following approaches you can use in your code to get required 
> behavior:
> 
> 1) As suggested below use the approach with Serializable + 
> serialVersionUID. It will work;
> 
> 2) More preferable is to have different implementations with different 
> names (ExampleServiceImpl1, ExampleServiceImpl2, etc...). Is there any 
> reasons you can't use this straightforward approach?
> When the implementations are ready you can put their classes onto every 
> machine in order to have them in the classpath or you can leverage 
> IgniteConfiguration.peerClassLoadingEnabled feature.
> The feature allows to load missing classes from a machine that sends 
> compute based tasks onto a machine that will execute a task and you don't 
> need to copy implementations' classes manually at all.
> You can read more on this here: 
> 

Re: OptimizedClassDescriptor verifyChecksum object set as optional

[Denis Magda]

Hi,

As I understand both servers have different implementations but the 
names of those implementations are the same, correct?
Because otherwise I don't see how your code could get to the point of 
checksum validation if one implementation's name is ServiceEntity while 
the other's is DataEntity.


If my assumptions above are correct then I would recommend to do the 
following:


1) Extend Serializable instead of Externalizable

interface Entity extends Serializable {
.
}

2) Add custom serialVersionUID to each implementation. This will help 
you get rid off checksum related exception


class EntityImpl implements Entity {

private static final long serialVersionUID =0L;

..
}


Regards,
Denis

On 11/8/2015 3:27 PM, 姜 为 wrote:

Hi guys:

I’m using ignite 1.4.
In IgniteCompute.call will transfer of an object to the cluster.
 The object should implement Serializable or Externalizable interface.
 OptimizedClassDescriptor.read method will check whether the object is in 
the same class.

 In my use case,I have some type of servers in cluster.
 The server type A will check the business,and the server type B will 
persistent data.
 There is a entity interface Entity extends Externalizable have different 
implementations on different servers.
 Such like this:

 interface Entity extends Externalizable {
method a();
method b();
method c();
}

class  ServiceEntity implements Entity {
method a(){
// do something...
}

method b(){
// do something...
}

method c(){
throw new UnsupportedException...
}

Externalizable.read...
Externalizable.write...
 }

 class DataEntity implements Entity {
method a(){
// do something...
}

method b(){
throw new UnsupportedException...
}

method c(){
// do something...
}

Externalizable.read...
Externalizable.write...
 }


 And IgniteCompute.call(new IgniteCallable(
public Object call(){
Entity.a() or b and c;..
}
));

Different implementations of the same class are to achieve read and write 
methods.
But OptimizedClassDescriptor.read will check the class sum and throw 
ClassNotFoundException.

I recommend verifyChecksum object set as optional,and I really need is 
change.

Here is my pr:
https://issues.apache.org/jira/browse/IGNITE-1854 

   https://github.com/apache/ignite/pull/200/ 

Re: OptimizedClassDescriptor verifyChecksum object set as optional

[Valentin Kulichenko]

Hi,

I'm against optional checksum verification. It's not safe, adds one more
configuration property and I don't see any use case that can require this.

I also don't completely understand what you're trying to achieve. Can you
please describe the sequence of serialization/deserialization events that
you expect in your application?

-Val

On Mon, Nov 9, 2015 at 5:13 PM, 姜 为  wrote:

> Hi:
>
> The implementations name maybe not same.
>
> Like my example:
>
> class DataEntity {
> Integer id;
> string name;
> Integer age;
>
> ….. and other
>
> Externalizable.read(in){
> if(in.readBoolean()) {
> id = in.readInt();
> }
> same as name,age...
> }
>
> Externalizable.write(out){
> out.writeBoolean(id != null);
> if(id != null) {
> out.writeInt(id);
> }
> same as name,age...
> }
> }
>
> class ServiceEntity {
> Integer id;
> Integer age;
>
> …. and other
>
> Externalizable.read(in){
> if(in.readBoolean()) {
> id = in.readInt();
> }
> if(in.readBoolean()) {
> in.readString(); // ignore name
> }
> if(in.readBoolean()) {
> age = in.readInt();
> }
> … and other
> }
>
> Externalizable.write(out){
> out.writeBoolean(id != null);
> if(id != null) {
> out.writeInt(id);
> }
> out.writeBoolean(false); // null for name
>out.writeBoolean(age != null);
> if(age != null) {
> out.writeInt(age);
> }
> … and other
> }
> }
>
> The other implementation class can be serialized and deserialized
> custom rules by Externalizable.read and Externalizable.write.
> Each of the different types of servers property needs are
> different,it does not require a complete serialization.
>
>
>
>
> > 在 2015年11月9日，下午10:22，Denis Magda  写道：
> >
> > Hi,
> >
> > As I understand both servers have different implementations but the
> names of those implementations are the same, correct?
> > Because otherwise I don't see how your code could get to the point of
> checksum validation if one implementation's name is ServiceEntity while the
> other's is DataEntity.
> >
> > If my assumptions above are correct then I would recommend to do the
> following:
> >
> > 1) Extend Serializable instead of Externalizable
> >
> > interface Entity extends Serializable {
> > .
> > }
> >
> > 2) Add custom serialVersionUID to each implementation. This will help
> you get rid off checksum related exception
> >
> > class EntityImpl implements Entity {
> > private static final long serialVersionUID = 0L;
> > ..
> > }
> >
> >
> > Regards,
> > Denis
> >
> > On 11/8/2015 3:27 PM, 姜 为 wrote:
> >> Hi guys:
> >>
> >>  I’m using ignite 1.4.
> >>  In IgniteCompute.call will transfer of an object to the cluster.
> >> The object should implement Serializable or Externalizable
> interface.
> >> OptimizedClassDescriptor.read method will check whether the object
> is in the same class.
> >>
> >> In my use case,I have some type of servers in cluster.
> >> The server type A will check the business,and the server type B
> will persistent data.
> >> There is a entity interface Entity extends Externalizable have
> different implementations on different servers.
> >> Such like this:
> >>
> >> interface Entity extends Externalizable {
> >>  method a();
> >>  method b();
> >>  method c();
> >>  }
> >>
> >>  class  ServiceEntity implements Entity {
> >>  method a(){
> >>  // do something...
> >>  }
> >>
> >>  method b(){
> >>  // do something...
> >>  }
> >>
> >>  method c(){
> >>  throw new UnsupportedException...
> >>  }
> >>
> >>  Externalizable.read...
> >>  Externalizable.write...
> >> }
> >>
> >> class DataEntity implements Entity {
> >>  method a(){
> >>  // do something...
> >>  }
> >>
> >>  method b(){
> >>  throw new UnsupportedException...
> >>  }
> >>
> >>  method c(){
> >>  // do something...
> >>  }
> >>
> >>  Externalizable.read...
> >>  Externalizable.write...
> >> }
> >>
> >>
> >> And IgniteCompute.call(new IgniteCallable(
> >>  public Object call(){
> >>  Entity.a() or b and c;..
> >>  }
> >>  ));
> >>
> >>Different implementations of the same class are to achieve read 

Re: OptimizedClassDescriptor verifyChecksum object set as optional

[姜 为]

Hi:

The implementations name maybe not same.

Like my example:

class DataEntity {
Integer id;
string name;
Integer age;

….. and other

Externalizable.read(in){
if(in.readBoolean()) {
id = in.readInt();
}
same as name,age...
}

Externalizable.write(out){
out.writeBoolean(id != null);
if(id != null) {
out.writeInt(id);
}
same as name,age...
}
}

class ServiceEntity {
Integer id;
Integer age;

…. and other 

Externalizable.read(in){
if(in.readBoolean()) {
id = in.readInt();
}
if(in.readBoolean()) {
in.readString(); // ignore name
}
if(in.readBoolean()) {
age = in.readInt();
}
… and other
}

Externalizable.write(out){
out.writeBoolean(id != null);
if(id != null) {
out.writeInt(id);
}
out.writeBoolean(false); // null for name
   out.writeBoolean(age != null);
if(age != null) {
out.writeInt(age);
}
… and other
}
}

The other implementation class can be serialized and deserialized 
custom rules by Externalizable.read and Externalizable.write.
Each of the different types of servers property needs are different,it 
does not require a complete serialization.




> 在 2015年11月9日，下午10:22，Denis Magda  写道：
> 
> Hi,
> 
> As I understand both servers have different implementations but the names of 
> those implementations are the same, correct?
> Because otherwise I don't see how your code could get to the point of 
> checksum validation if one implementation's name is ServiceEntity while the 
> other's is DataEntity.
> 
> If my assumptions above are correct then I would recommend to do the 
> following:
> 
> 1) Extend Serializable instead of Externalizable 
> 
> interface Entity extends Serializable {
> .
> }
> 
> 2) Add custom serialVersionUID to each implementation. This will help you get 
> rid off checksum related exception
> 
> class EntityImpl implements Entity {
> private static final long serialVersionUID = 0L;
> ..
> }
> 
> 
> Regards,
> Denis 
> 
> On 11/8/2015 3:27 PM, 姜 为 wrote:
>> Hi guys:
>> 
>>  I’m using ignite 1.4.
>>  In IgniteCompute.call will transfer of an object to the cluster.
>> The object should implement Serializable or Externalizable interface.
>> OptimizedClassDescriptor.read method will check whether the object is in 
>> the same class.
>> 
>> In my use case,I have some type of servers in cluster.
>> The server type A will check the business,and the server type B will 
>> persistent data.
>> There is a entity interface Entity extends Externalizable have different 
>> implementations on different servers.
>> Such like this:
>> 
>> interface Entity extends Externalizable {
>>  method a();
>>  method b();
>>  method c();
>>  }
>> 
>>  class  ServiceEntity implements Entity {
>>  method a(){
>>  // do something...
>>  }
>> 
>>  method b(){
>>  // do something...
>>  }
>> 
>>  method c(){
>>  throw new UnsupportedException...
>>  }
>> 
>>  Externalizable.read...
>>  Externalizable.write...
>> }
>> 
>> class DataEntity implements Entity {
>>  method a(){
>>  // do something...
>>  }
>> 
>>  method b(){
>>  throw new UnsupportedException...
>>  }
>> 
>>  method c(){
>>  // do something...
>>  }
>> 
>>  Externalizable.read...
>>  Externalizable.write...
>> }
>> 
>> 
>> And IgniteCompute.call(new IgniteCallable(
>>  public Object call(){
>>  Entity.a() or b and c;..
>>  }
>>  ));
>> 
>>Different implementations of the same class are to achieve read and write 
>> methods.
>>But OptimizedClassDescriptor.read will check the class sum and throw 
>> ClassNotFoundException.
>> 
>>I recommend verifyChecksum object set as optional,and I really need is 
>> change.
>> 
>>Here is my pr:
>>https://issues.apache.org/jira/browse/IGNITE-1854 
>>  
>>  
>> 
>>   https://github.com/apache/ignite/pull/200/ 
>>  
>>  
>>