Passing a file parameter to Java from C

Question

Hi everyone
I am writing a dll which calls some java methods. One of these methods takes a File parameter. The lookup of the method id is successful, but I do not know how to convert the pFile pointer ( initailised by fopen() ) into a jobject reference. I can't find any examples inthe documentation and forums. Can anyone help?
thanks
               /* get the required method*/                                    
               id = env->GetMethodID(cls, methodName, "(Ljava/io/File;)I");  
               if (id == 0)
               fprintf(stderr, "Can't find method\n");
               return(FAIL);
          /* File parameter, int return type */
          /* cast param to the correct type  */
          jobject fileParam = (jobject)pFile;    
               /*  !!!      Does not work, Java throws a null pointer exception  */
          /* call the java method  */
          result = env->CallIntMethod(objLCM, id, fileParam);

Answer 1

of the method id is successful, but I do not know how
to convert the pFile pointer ( initailised by
fopen() ) into a jobject reference. I can't find anyYou can't do this. It is not possible. Beyond that, your file pointer is probably a result of calling fopen(...) or something, right? the java object File is just a reference to a resource, not an open, readable/writable resource. You can think of it sort of like a URL.
Best thing to do to try to spoof this might be to create an intermediate layer in java that takes the file name from C and converts it into a File. If you need to write to the file, you're going to need an outputstream or a Writer object, which is a whole different mess
good luck