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Java Socket doesn't return anything in the stream

When I try to get information from a Socket (it's at localhost) it never returns what I want (info from my server) with php it works fine..

Java application: run & debug doesn't return anything
Glassfish server: run doesn't return anything, debug return all the info, everytime i debug

PHP Code:

$Socket = fsockopen($this->Host, $this->Port, $errno, $errstr, 5);
    if(!$Socket) {
    return false;
} else {

    stream_set_timeout($Socket, 1);
    stream_set_blocking($Socket, false);

    fwrite($Socket, chr(6).chr(0).chr(255).chr(255).'info');
    while(!feof($Socket)) {
        $this->SocketData .= fgets($Socket, 8192);
    }
    fclose($Socket);
    return true;
}


Java Code:

public static String serverInfo(String ip, Integer port) {
    try (Socket socket = new Socket(ip, port)) {
        //System.out.println("Connected to " + socket.getInetAddress() + " on port " + socket.getPort() + " from port " + socket.getLocalPort() + " of " + socket.getLocalAddress());

        OutputStream os = socket.getOutputStream();
        String info = ((char) 6 + "" + (char) 0 + "" + (char) 255 + "" + (char) 255 + "info");
        System.out.println(info);
        os.write(info.getBytes());

        BufferedReader br = new BufferedReader(new InputStreamReader(socket.getInputStream()));

        StringBuilder stb = new StringBuilder();
        while (br.ready()) {
            stb.append(br.readLine());
        }
        if (!stb.toString().isEmpty()) {
            //System.out.println("Info: " + stb.toString());
            return stb.toString();
        } else {
            //System.out.println("No answer from server.");
            return null;
        }
    } catch (UnknownHostException e) {
        System.err.println("I can't find " + ip);
    } catch (SocketException e) {
        System.err.println("Could not connect to " + ip);
    } catch (IOException e) {
        System.err.println(e);
    }
    return null;
}


What I was looking for, was to do the same as php does, connect to the socket, get the information and return/save/whatever with that information and I don't know what happens that only 1/100 times that I try, it returns something.
When I run in my web application AND debug, it returns EVERYTIME the info, something is really wrong and I can't figure it out..

PS: It's meant to get OTServer information.

I think this is not the right way to read from the br .

while (br.ready()) {
        stb.append(br.readLine());
}

Try changing this to:

String line = null;
while ((line = br.readLine()) != null) {
        stb.append(line);
}

Also, call os.close() after this line.

os.write(info.getBytes());

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