Android - Descargar sitio en cache

public class MainActivity extends AppCompatActivity {

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        supportRequestWindowFeature(Window.FEATURE_NO_TITLE);

        setContentView(R.layout.activity_main);

        this.webView = (WebView) this.findViewById(R.id.webview);

        WebSettings webSettings = webView.getSettings();

        webView.setWebViewClient(new WebViewClient());

        webView.getSettings().setAppCachePath(getApplicationContext().getCacheDir().getAbsolutePath());

        webView.getSettings().setAllowFileAccess(true);

        webView.getSettings().setAppCacheEnabled(true);

        webView.getSettings().setJavaScriptEnabled(true);

        webView.getSettings().setCacheMode(WebSettings.LOAD_DEFAULT); // load online by default

        if (!isNetworkAvailable()) { // loading offline

            //webView.getSettings().setCacheMode(WebSettings.LOAD_CACHE_ELSE_NETWORK);

            webView.getSettings().setCacheMode(WebSettings.LOAD_CACHE_ONLY);

        }

        webView.loadUrl("http://www.misitio.com");

    }

    private boolean isNetworkAvailable() {

        ConnectivityManager connectivityManager = (ConnectivityManager) getSystemService(CONNECTIVITY_SERVICE);

        NetworkInfo activeNetworkInfo = connectivityManager.getActiveNetworkInfo();

        return activeNetworkInfo != null && activeNetworkInfo.isConnected();

    }

    @Override

    public boolean onKeyDown(int keyCode, KeyEvent event) {

        if ((keyCode == KeyEvent.KEYCODE_BACK) && this.webView.canGoBack()) {

            this.webView.goBack();

            return true;

        }

        return super.onKeyDown(keyCode, event);

    }