***********************************************************
java code
**********************************************************
  public void Send(Object   buf,
                   int      offset, 
                   int      count, 
                   Datatype type,
                   int      dest,  
                   int      tag) {

    if (type.isObject(type)){   
      byte[] byte_buf = Object_Serialize(buf,offset,count,type);

      int[] length_buf = new int[2];
      length_buf[0] = byte_buf.length; 
      length_buf[1] = count; 
      Send(length_buf,0, MPI.INT.Size(),2,MPI.INT, dest, tag);
      Send(byte_buf,0,MPI.BYTE.Size(),length_buf[0],MPI.BYTE,dest, tag);

      if(isVector){
        SendVector(vector,dest, tag);
      }
    }	 
    else Send(buf,             offset, 
              type.baseSize(), count, 
              type,            dest, 
              tag);
  }
  
  private native void SendVector(Object vector,
                            int    dest, 
                            int    tag);

  public Status Recv(Object   buf, 
                     int      offset, 
                     int      count, 
                     Datatype type,
                     int      source, 
                     int      tag) {

    if (type.isObject(type)){
      Status status = new Status();
      int[] length_buf= new int[2];
     
      Recv(length_buf,0,2, MPI.INT, source, tag, new Status()); 
      byte[] byte_buf = new byte[length_buf[0]];
    	   	
      Recv(byte_buf,0,length_buf[0], MPI.BYTE, source, tag,status);       
      status.object_count = length_buf[1];

      Object_Deserialize(buf,byte_buf,offset,length_buf[1],type);
      if (isVector){
        RecvVector(vector,source,tag);
      }
      return status;
    }
    else return Recv(buf,    offset*type.baseSize(),
                     count,  type,
                     source, tag, 
                     new Status());
  }

  private native void RecvVector(Object buf,
                                 int source,
                                 int tag);

*******************************************************88
c code
*********************************************************
 JNIEXPORT void JNICALL Java_mpi_Comm_SendVector
   (JNIEnv *env, jobject jthis, jobject buf, jint dest, jint tag)



 JNIEXPORT void JNICALL Java_mpi_Comm_RecvVector
   (JNIEnv *env, jobject jthis, jobject buf, jint source, jint tag)