Send file with RMI

Question

Hi,
I tried to send a file from client to server with RMI as follow:
upload(String filename, InputStream in);
however the InputStream is not a Serializable.
1. Is it a correct method to send the file in RMI ? if not, what should be used?
2. How to "Serialize" the InputStream, I have tried to pass the "SerailInputStream" extends from InupStream object implements Serializable as a byte array by the ObjectOutputStream and retrieve it in server successfully, but the inputstream seems cannot be used.
Many thanks
George

Answer 1

PipedIn/OutStreams used to commnicate inter-thread transfer. I guess bschauwe are guiding the way how to smoothly handle the file transfer inside the server. The communication to server seems not through the java streams classes.
if what you want to do is to copy a file in whole. You may send a byte array in a serializable wrapper class. You can create a byte array of a file by using ByteArrayOutputStream and call toByteArray(). Finally in the server side, with the raw byte array, you can create a new ByteArrayInputStream(byte[]). You know the rest of story.
Or you can create a serializable class that extends InputStream and similary behaves like ByteArrayIn/OutStream. In this case, you have to know how to make a sub-class of non-serializable super class serializable. There is tutorial in the SUN site covering this subject. If you also look at the source codes of both InputStream and ByteArrayInputStream, there is no rocket-science there.
Frankly, I have not tried myself yet. I am also looking forward to hearing the better suggestion.
Hope it helped.