SMPP: how to create a simple listener in Java?

Question

I have a client which can generate and send SMS message by using SMPP protocol. I can setup on the client side destination address and user, password.

I would like to create a very simple server (listener) which will receive message (without SSL) from client side and write results in a file. I have found a lot of articles on this topic, but they didn't help me.

Could you suggest the best way for solving this issue?

Answer 1

This is a very simple way. Since you have client I assume there is a way to encode/decode bytes into SMPP packet.

public void runServer() throws Exception
{
    ServerSocket serverSocket = new ServerSocket(6868);
    Socket socket = serverSocket.accept();
    while (socket.isBound()) {
        byte[] bytes = readBytes(socket.getInputStream()) ;
        - encode bytes to smpp
        - create smpp response and decode to bytes
        socket.getOutputStream().write(bytes);
        socket.getOuptutStream().flush();
    }
    socket.close();
    serverSocket.close();
}

private byte[] readBytes(InputStream is) throws Exception
{
    ByteArrayOutputStream baos = new ByteArrayOutputStream();
    int i ;
    while ((i=is.read()) != -1) baos.write(i);
    return baos.toByteArray();
}

If you want more bullet proof code, then after server accept you create a worker thread, which runs separately, while server is accepting another connections.