Sockets in J2ME

[feda alshahwan]

I have the followingcode that reads data from input socket and then casted to HTTPConnection to allow using HTTP methods but it is giving me casting exception errorHow can I do it " Read string from input stream and get the http header information andbody information from it" Thanks

  
        public class RequestHandler extends Thread{
          SocketConnection sc;
          HttpConnection sch;
             RequestHandler (SocketConnection sc){
                 this.sc=sc;
                 System.out.println("passedb");
                 start();
                  }
             public void run(){
                 try{
                     System.out.println("Going to read data...");
                    int ch = 0;
                    String reqMessage= "";
                    while(ch != 23  && ch != 13 )
                   {
                    ch = is.read();
                    reqMessage=reqMessage+(char)ch;
                     }
                   
                   
                   form.append(reqMessage);
                   sch=(HttpConnection)sc;
                   sch.getRequestMethod();
                   System.out.println("The request method is: "+sch.getRequestMethod()+"\n");
                   is.close();  

[Srinivas Vurrinkala]

Hi you cant typecast the socketconnection to httpconnection. You have to decide which connection had to be used. If you want header information while opening the connection typecast that to HttpConnection that is the standard way we do in J2ME.

HttpConnection conn =(HttpConnection)Connector.open(url);

[feda alshahwan]

Thank you for assistance my requirement is: The client wants to communicate with a server that provides restful web services.
So the client will send for example (GET /Addition?q1=5&q2=6 HTTP1.1) and the server will should parse the received message and extract the Addition and parameters and redirect it to the appropriate resource? So what is the best solution?

[Srinivas Vurrinkala]

I got what you want to do. For invoking restful services you just need to construct http url with above said parameters . The url can be this http://somesite.com/addition?q1=5&q2=6. This will definitely works out.


Regards
Srinivas

[feda alshahwan]

I did what you told me but I got the following error:
Uncaught exception java/lang/IllegalArgumentException: Malformed address.
knowing that the code is:

   public void run(){
      String respMessage = "";
        try{
// Create a request to connect to Server.
        HttpConnection httpc = (HttpConnection)
                         Connector.open("socket://localhost:30000/Addition/q1=5&@q2=7");
        form.append("Client requesting a connection....");

// Get the input stream of the connection.
        DataInputStream is  = httpc.openDataInputStream();
// Get the output stream of the connection.
        DataOutputStream os = httpc.openDataOutputStream();
// Send Message.  

The server side code is:

  
   public class RESTServerMidlet extends MIDlet implements CommandListener,Runnable{
    private Form form=new Form("Creating RESTFul Mobile Web Server");
    private Command startservercommand =new Command("Start Server",Command.OK,1);
    private StringItem stringitem = new StringItem("Server","IF You Want to Start Server Press Start Server Button");
    private Display display;

    
    public void startApp() {
        form.append(stringitem);
        form.addCommand(startservercommand);
        Display.getDisplay(this).setCurrent(form);
        form.setCommandListener(this);
    }

    public void pauseApp() {
    }

    public void destroyApp(boolean unconditional) {
    }
    public void commandAction(Command c, Displayable d)
    {
        try
        {
            if (c==startservercommand)
            {
                Thread t =new Thread(this);
                t.start();
            }
        }catch(Exception e)
            {

            }
        }
        public void run(){
               ServerSocketConnection scn =null;
            try{
                scn=(ServerSocketConnection) Connector.open("socket://:30000");

            }catch (IOException ex){
                ex.printStackTrace();
        }
            while (true)
            {
                try{
                    form.append("Waiting for Client Request........");
                    HttpConnection httpc=null;
                    //HttpConnection httpc;
                    System.out.println("PASS1");
                    httpc= (HttpConnection)scn.acceptAndOpen();
                      System.out.println("PASScaasting problem");
                    form.append("Request Accepted on host address :"+scn.getLocalAddress()+" And on Port number:" +scn.getLocalPort());
    //               String url = scn.getLocalAddress();
                  //  httpc= (HttpConnection) Connector.open("http://"+url);
                    //httpc =(HttpConnection) sc;
                    System.out.println("PASS2");
                    //form.append("Request Accepted on host address :"+scn.getLocalAddress()+" And on Port number:" +scn.getLocalPort());
                    RequestHandler RH=new RequestHandler (httpc);

                }catch (IOException ex){
                    ex.printStackTrace();
                }
            }
    }
        public class RequestHandler extends Thread{
            HttpConnection httpc;
           
            String requestMethod;
            RequestHandler (HttpConnection httpc){
                this.httpc=httpc;
                start();
            }
            public void run(){
                System.out.println("passedc");
               DataInputStream is ;
               DataOutputStream os;
            try {
                is = httpc.openDataInputStream();

                os = httpc.openDataOutputStream();
                String query=httpc.getQuery();
                form.append("The query is :"+query);
                           }
            catch (IOException ex) {
                ex.printStackTrace();
            }        }
}}