[vtkusers] Returning datas as java array

[Simon Chatelain]

Jarek Sacha wrote:

>--- Simon Chatelain <simon.chatelain at epfl.ch> wrote:
>  
>
>>Hello,
>>i'm still trying to transfer my vtkimageData via Java-RMI. But now, i'am
>>
>>trying to subclass vtkImageData to add a method who return
>>all the datas as a byte array. And i want to call this method from Java 
>>to reiceve a java Byte Array (byte[]) but if the C++ method return a
>>char*
>>the wrapper understand that as returning a java String.
>>    
>>
>
>[I did not follow what you were doing before, not sure what wrapper you
>mean above.]
>
>You can convert String to byte[] either using String.getBytes() method or
>CharacterEncoder class (new Java 1.4).
>
>Jarek
>
>  
>
Hello,

The wrapper i mentionned is the vtkWrappJava executable who generate the 
JNI c++ and java class.
And the problem is that c++ char type is a 8 bits type and the Java char 
who compose a String is 16 bit unicode
character. So i cannot recast the string into byte, the datas are not 
similar.

The general problem is to transfer a vtkImageData from a java 
application to another via the Java-RMI system.
The first solution is to serialize the object, but as the java 
vtkImageData  object is a wrapp class to an c++ object,
i do'nt know how to serialize it. If i do this simply, only the java 
object is transferred and not the data stored into
the C++ object.

So,now, the idea is to get the datas of the imageData as a raw byte 
array, who is a type easily serializable, then i transfer
this raw data via RMI, and i reconstruct a vtkImageData object on the 
other side.
My question is how to code a method in C++ who return this raw byte 
array independently of the data type
 (float, int, unsigned int, etc...),  and who (after the generation of 
wrapping class process) return a jarray of byte and not a String ?

Thanks

Simon