Getting "java.net.ProtocolException: Server redirected too many times" Error

It's apparently redirecting in an infinite loop because you don't maintain the user session. The session is usually backed by a cookie. You need to create a CookieManager before you use URLConnection.

// First set the default cookie manager.
CookieHandler.setDefault(new CookieManager(null, CookiePolicy.ACCEPT_ALL));

// All the following subsequent URLConnections will use the same cookie manager.
URLConnection connection = new URL(url).openConnection();
// ...

connection = new URL(url).openConnection();
// ...

connection = new URL(url).openConnection();
// ...

See also:

• Using java.net.URLConnection to fire and handle HTTP requests

Duse, I have add this lines:

java.net.CookieManager cm = new java.net.CookieManager();
java.net.CookieHandler.setDefault(cm);

See this example:

java.net.CookieManager cm = new java.net.CookieManager();
java.net.CookieHandler.setDefault(cm);
String buf="";
dk = new DAKABrowser(input.getText());
try {
    URL url = new URL(dk.toURL(input.getText()));
    DataInputStream dis = new DataInputStream(url.openStream());
    String inputLine;
    while ((inputLine = dis.readLine()) != null) {
        buf+=inputLine;
        output.append(inputLine+"\n");
    }
    dis.close();
} 
catch (MalformedURLException me) {
    System.out.println("MalformedURLException: " + me);
}
catch (IOException ioe) {
    System.out.println("IOException: " + ioe);
}
titulo.setText(dk.getTitle(buf));