App connects to the server but can not communicate

Question

I apologize in advance for my bad english

The app is able to connect to the server java, but hangs at the time of the exchange of data.

This is the client android code:

@SuppressLint("NewApi")
public class Connection extends IntentService{

private String tag = "Ciclo eventi";
private String user;
private String pass;

public Connection()
{
    super("Connection");
}

public void onCreate(){
    super.onCreate();
    StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
    StrictMode.setThreadPolicy(policy);
}

public void onStart(Intent intent, int startId){

    Log.d(tag, "GetData");
    Bundle extras = intent.getExtras();
    user = (String) extras.get("User");
    pass = (String) extras.get("Password");
    Log.d(tag, user);
    Log.d(tag, pass);
    onHandleIntent(intent);
}

public int onStartCommand(Intent intent, int flags, int startId){
    onHandleIntent(intent);
    return START_NOT_STICKY;
}



@Override
public void onDestroy()
{
    Log.d(tag, "CONNECTION CLOSED");

}

@Override
protected void onHandleIntent(Intent intent) {
    Socket s=null;
    BufferedReader in=null;
    PrintWriter  writer=null;
    try {
        Log.d(tag, "Try to connect");
        s = getConnection("192.168.1.103", 5433);
        Log.d(tag, "Connection done");
        in = new BufferedReader(new InputStreamReader(s.getInputStream()));
        writer = new PrintWriter(s.getOutputStream(), true);
        writer.println(user);
        writer.println(pass);
        Log.d(tag, "I've send the credential");
        String resp = null;
        resp = in.readLine();
        Log.d(tag, "Receive the results");
        if(resp.equals("done")){
            Log.d(tag, "ACCEPT");
            /*Intent i=new Intent(this,SecondActivity.class);
            startActivity(i);*/
            onDestroy();
        }
        else{
            Log.d(tag, "Refused");
        }
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }


}

protected Socket getConnection(String ip, int port) throws IOException  {
    try {
        KeyStore trustStore = KeyStore.getInstance("BKS");
        InputStream trustStoreStream = getApplicationContext().getResources().openRawResource(R.raw.server);
        trustStore.load(trustStoreStream, "keypass".toCharArray());

        TrustManagerFactory trustManagerFactory = TrustManagerFactory.getInstance(KeyManagerFactory.getDefaultAlgorithm());
        trustManagerFactory.init(trustStore);

        SSLContext sslContext = SSLContext.getInstance("TLS");
        sslContext.init(null, trustManagerFactory.getTrustManagers(), null);
        SSLSocketFactory factory = sslContext.getSocketFactory();
        SSLSocket socket = (SSLSocket) factory.createSocket(ip, port);
        //socket.setEnabledCipherSuites(getCipherSuitesWhiteList(socket.getEnabledCipherSuites()));
        return socket;
    } catch (GeneralSecurityException e) {
        Log.e(this.getClass().toString(), "Exception while creating context: ", e);
        throw new IOException("Could not connect to SSL Server", e);
    }
}


    public static String[] getCipherSuitesWhiteList(String[] cipherSuites) {
        List<String> whiteList = new ArrayList<>();
        List<String> rejected = new ArrayList<>();
        for (String suite : cipherSuites) {
            String s = suite.toLowerCase();
            if (s.contains("anon") || //reject no anonymous
                    s.contains("export") || //reject no export
                    s.contains("null") || //reject no encryption
                    s.contains("md5") || //reject MD5 (weaknesses)
                    s.contains("_des") || //reject DES (key size too small)
                    s.contains("krb5") || //reject Kerberos: unlikely to be used
                    s.contains("ssl") || //reject ssl (only tls)
                    s.contains("empty")) {    //not sure what this one is
                rejected.add(suite);
            } else {
                whiteList.add(suite);
            }
        }
        return whiteList.toArray(new String[whiteList.size()]);
    }}

I need a service because i need a syncronous thread

This is the java server code:

public class SocketThread implements Runnable{
private Socket s1;
private BufferedReader in;
private PrintWriter out;
private String user = "admin";
private String pass = "ciao";

SocketThread(Socket s){
    this.s1=s;
}

public void run(){
    boolean loginDone = false;
    String user1 = null;
    String password1 = null;
    String lati = null;
    String longi = null;
    String via = null;
    System.out.println("Connected");
    try {
        in = new BufferedReader(new InputStreamReader(s1.getInputStream()));
        out = new PrintWriter(s1.getOutputStream(), true);
        user1 = in.readLine();
        password1 = in.readLine();
        System.out.println("User : "+user1+" Password : "+ password1);
    } catch (IOException e) {
        // TODO Auto-generated catch block
        System.out.println("error on buffer creation");
        e.printStackTrace();
    }
    System.out.println("Access done, wait for check credential");
    do{
    if(user1.compareTo(user)==0 && password1.compareTo(pass)==0){
        loginDone = true;
        out.println("done");

    }
    else{
        out.println("noaccess");

    }
    }while(loginDone == false);
    System.out.println("Login done");
    try {
        System.out.println("Close done");
        s1.close();
        in.close();
        out.close();
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

    System.out.println("Thread off");
}}

Both the server and client crashes with no message error when exchanging data (both input and output)

The network is ok, the privileges of the android app are .INTERNET, .ACCESS_WIFI_STATE, .ACCESS_NETWORK_STATE

The server works well with a Java Desktop Client.

Thank you very much!

Answer 1

try using Volley

https://developer.android.com/training/volley/index.html

you can also use custom requests with volley.

https://developer.android.com/training/volley/index.html