How to connect via FTP on Android?

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How to connect via FTP on Android?

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#1 by (3 votes)
#2 by (0 votes)

2

I am trying to connect locally to the FTP server to recover some files and read them.

The program peta when making the connection to the server "localhost".

02-02 11: 34: 38.472 3867-3867 / com.mimapa E / AndroidRuntime: FATAL EXCEPTION: main Process: com.mimapa, PID: 3867 java.lang.RuntimeException: Unable to start activity ComponentInfo {com.image / com.image.CreatModify}: android.os.NetworkOnMainThreadException at android.app.ActivityThread.performLaunchActivity (ActivityThread.java:2665) at android.app.ActivityThread.handleLaunchActivity (ActivityThread.java:2726) at android.app.ActivityThread.-wrap12 (ActivityThread.java) at android.app.ActivityThread $ H.handleMessage (ActivityThread.java:1477) at android.os.Handler.dispatchMessage (Handler.java:102) at android.os.Looper.loop (Looper.java:154) at android.app.ActivityThread.main (ActivityThread.java:6119) at java.lang.reflect.Method.invoke (Native Method) at com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run (ZygoteInit.java:886) at com.android.internal.os.ZygoteInit.main (ZygoteInit.java:776) Caused by: android.os.NetworkOnMainThreadException at android.os.StrictMode $ AndroidBlockGuardPolicy.onNetwork (StrictMode.java:1303) at java.net.Inet6AddressImpl.lookupHostByName (Inet6AddressImpl.java:86) at java.net.Inet6AddressImpl.lookupAllHostAddr (Inet6AddressImpl.java:74) at java.net.InetAddress.getByName (InetAddress.java:708) at org.apache.commons.net.SocketClient.connect (SocketClient.java:203) at com.utils.FtpControl.connect (FtpControl.java:101) at com.mimapa.CreateModify.readArchives (CreateModify.java:65) at com.mimapa.CreatModify.onCreate (CreateModify.java:39) at android.app.Activity.performCreate (Activity.java:6679) at android.app.Instrumentation.callActivityOnCreate (Instrumentation.java:1118) at android.app.ActivityThread.performLaunchActivity (ActivityThread.java:2618) at android.app.ActivityThread.handleLaunchActivity (ActivityThread.java:2726) at android.app.ActivityThread.-wrap12 (ActivityThread.java) at android.app.ActivityThread $ H.handleMessage (ActivityThread.java:1477) at android.os.Handler.dispatchMessage (Handler.java:102) at android.os.Looper.loop (Looper.java:154) at android.app.ActivityThread.main (ActivityThread.java:6119) at java.lang.reflect.Method.invoke (Native Method) at com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run (ZygoteInit.java:886) at com.android.internal.os.ZygoteInit.main (ZygoteInit.java:776)

On the other hand I have programmed the same class but in NetBeans and the operation is correct, I can connect and read the files. I only have the problem with Android Studio.

public class MainActivity extends AppCompatActivity {     Button btMapas;

@Override protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    btMapas = (Button) findViewById(R.id.btMapa);
    btMapas.setEnabled(true);

    leerArchivos(); }


private void leerArchivos() {
    BufferedReader br = null;
    FtpControl ftpControl = new FtpControl("localhost", "userftp", "admin");
    ftpControl.conectar();
    String[] lista = ftpControl.listaArchivos("/srv/ftp/");
    try {
        for (int i = 0; i < lista.length; i++) {
            br = ftpControl.descargarArchivo("/srv/ftp/" + lista[i]);
            if (br != null) {
                guardarUsuario(
                        br.readLine(),
                        br.readLine(),
                        br.readLine(),
                        br.readLine()
                );
            }
            br.close();
        }

        ftpControl.cerrar();
    } catch (Exception e) {
        e.printStackTrace();
    }

}

private void guardarUsuario(String nombre, String lat, String log, String fecha) {
    MyDataBase admin = new MyDataBase(this,
            null, null, 1);
    ContentValues values = new ContentValues();
    // Pares clave-valor
    values.put(UsuarioContract.UsuarioEntry.ORGANIZACION, "Grupo A");
    values.put(UsuarioContract.UsuarioEntry.USUARIO_APP, 0);
    values.put(UsuarioContract.UsuarioEntry.USUARIO, nombre);
    values.put(UsuarioContract.UsuarioEntry.LONGITUD, log);
    values.put(UsuarioContract.UsuarioEntry.LATITUD, lat);
    values.put(UsuarioContract.UsuarioEntry.ACTIVADO, 0);
    Controlador.guardarUsuario(admin, values);
}

Connection class ftp:

public class FtpControl {

// datos
private  String servidor;
private  String usuario;
private  String pass;

private FTPClient cliente = null;

public FtpControl(String servidor, String usuario, String pass) {
    this.servidor = servidor;
    this.usuario = usuario;
    this.pass = pass;
}

public boolean subirArchivo(String path, String nombre) {
    FileInputStream fis = null;

    // si el usuario esta conectado al servidor
    if (cliente.isConnected()) {
        try {
            cliente.setFileType(FTP.BINARY_FILE_TYPE, FTP.BINARY_FILE_TYPE);
            cliente.setFileTransferMode(FTP.BINARY_FILE_TYPE);
            cliente.enterLocalPassiveMode();

            fis = new FileInputStream(path);
            cliente.storeFile(nombre, fis);
            cerrar(); // cerrar sesion
            return true;
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    return false;
}

public String[] listaArchivos(String path) {
    String[] lista = null;

    try {
        FTPFile[] ftpFiles = cliente.listFiles(path);
        int length = ftpFiles.length;
        lista = new String[length];
        for (int i = 0; i < length; i++) {
            String name = ftpFiles[i].getName();
            boolean isFile = ftpFiles[i].isFile();

            if (isFile) {
                lista[i] = name;
            } else {
                lista[i] = name;
            }
        }
        return lista;
    } catch (Exception e) {
        e.printStackTrace();
    }

    return lista;
}

public BufferedReader descargarArchivo(String path) {
    FileReader fr = null;
    BufferedReader br = null;

    try {
        fr = new FileReader(path);
        br = new BufferedReader(fr);
    } catch (Exception e) {
        e.printStackTrace();
    }

    return br;
}

public void conectar() {
    new Connection().execute();
}

public void cerrar() {
    try {
        cliente.logout();
        cliente.disconnect();
    } catch (IOException e) {
        e.printStackTrace();
    }
}



private class Connection extends AsyncTask<Void, Void, Void> {
    @Override
    protected Void doInBackground(Void... voids) {
        cliente = new FTPClient();

        try {
            // conectar al servidor
            cliente.connect(servidor, 21);
            cliente.login(usuario, pass);
        } catch (IOException e) {
            e.printStackTrace();
        }
        return null;
    }
    }  
}

java android ftp

asked by chdzma 02.02.2018 в 10:19

source

2 answers

0

Here is an example:

FTPClient ftpClient = new FTPClient();
ftpClient.connect(InetAddress.getByName(server));
ftpClient.login(user, password);
ftpClient.changeWorkingDirectory(serverRoad);
ftpClient.setFileType(FTP.BINARY_FILE_TYPE);

BufferedInputStream buffIn = null;
buffIn = new BufferedInputStream(new FileInputStream(file));
ftpClient.enterLocalPassiveMode();
ftpClient.storeFile("test.txt", buffIn);
buffIn.close();
ftpClient.logout();
ftpClient.disconnect();

I leave the link for more information: Here

answered by 02.02.2018 в 10:45

Data Structures (C) Send SMS Android

score 3 · Accepted Answer

The error you get is because you are doing operations on the main thread:

Caused by: android.os.NetworkOnMainThreadException

You can use as option a AsyncTask to execute the method leerArchivos() , it is not necessary to add all the code inside the AsyncTask only the call to the method:

 private class LeeArchivos extends AsyncTask<Void , Integer, Long>
    {
        @Override
        protected Long doInBackground(Void... voids) {
            leerArchivos();
            return null;
        }

        @Override
        protected void onPostExecute(Long result) {
          //Termina proceso
            Log.i("TAG" , "Termina proceso de lectura de archivos.");
        }
    }

In this way you would call the process:

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    btMapas = (Button) findViewById(R.id.btMapa);
    btMapas.setEnabled(true);

    //leerArchivos();
    new LeeArchivos().execute(); //*Llama AsyncTask.

}

Another option is to use runOnUiThread :

 runOnUiThread(new Runnable() {
        @Override
        public void run() {
            try {  

               leerArchivos(); //Realizar aquí tu proceso!                    

            } catch (Exception e) {
                Log.e("Error", "Exception: " + e.getMessage());
            }
        }
    });

Review a broader explanation of this error:

Error android.os.NetworkOnMainThreadException in using HttpURLConnection of Android