Re: Most efficient way to transfer a file directory recursively (using sockets)

From:
"Arash Nikkar" <anikkar@gmail.com>
Newsgroups:
comp.lang.java.programmer
Date:
22 Nov 2006 09:25:20 -0800
Message-ID:
<1164216320.545517.284990@h48g2000cwc.googlegroups.com>
Hi Red,

Thanks for the reply. One question though.

in the construct head method, what is all the CRLF stuff? thanks!

Red Orchid wrote:

"Arash Nikkar" <anikkar@gmail.com> wrote or quoted in
Message-ID: <1164154842.801238.263130@f16g2000cwb.googlegroups.com>:

I am trying to build a simple application which can be used much like a
ftp application, where the user will drag files over, and it will be
uploaded to a server.


To my thinking ....

<code>

//
// Main routine
//
OutputStream ou = ... // from socket.

File[] fs = getAllSendingFiles();

constructHead(ou, fs);
constructBody(ou, fs);
ou.flush();

// close stream and socket
...

//
// functions
//
File[] getAllSendingFiles() {
    // Maybe recursive is needed.
    return ...;
}

void constructHead(OutputStream out, File[] fs) throws IOException {

    StringBuilder head = new StringBuilder(8196);

    head.append("Protocol: Yours 1.0");
    head.append(CRLF);

    head.append("-"); // divider 1
    head.append(CRLF);

    for (File f : fs) {

        addFileHead(head, f);
    }
    head.append("---"); // divider 3
    head.append(CRLF);

    out.write(head.toString().getBytes("utf-8"));
}

void addFileHead(StringBuilder head, File f) {

    head.append("Path: " + f.getPath());
    head.append(CRLF);

    head.append("Length: " + f.length());
    head.append(CRLF);

// head.append("Type: Binary"); // or Text/UTF-8
// head.append(CRLF);

    head.append("--"); // divider 2
    head.append(CRLF);
}

void constructBody(OutputStream ou, File[] fs) throws IOException {

    for (File f : fs) {

        ou.write(getFileBytes(f));
    }
}

byte[] getFileBytes(File f) throws IOException {
    // from FileInputStream..
     return ...;
}

</code>

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