Connecting to remote URL which requires authentication using Java

Question

How do I connect to a remote URL in Java which requires authentication. I'm trying to find a way to modify the following code to be able to programatically provide a username/password so it doesn't throw a 401.

URL url = new URL(String.format("http://%s/manager/list", _host + ":8080"));
HttpURLConnection connection = (HttpURLConnection)url.openConnection();

Answer 1

You can set the default authenticator for http requests like this:

Authenticator.setDefault (new Authenticator() {
    protected PasswordAuthentication getPasswordAuthentication() {
        return new PasswordAuthentication ("username", "password".toCharArray());
    }
});

Also, if you require more flexibility, you can check out the Apache HttpClient, which will give you more authentication options (as well as session support, etc.)

Answer 2

There's a native and less intrusive alternative, which works only for your call.

URL url = new URL(“location address”);
URLConnection uc = url.openConnection();
String userpass = username + ":" + password;
String basicAuth = "Basic " + new String(Base64.getEncoder().encode(userpass.getBytes()));
uc.setRequestProperty ("Authorization", basicAuth);
InputStream in = uc.getInputStream();

Answer 3

You can also use the following, which does not require using external packages:

URL url = new URL(“location address”);
URLConnection uc = url.openConnection();

String userpass = username + ":" + password;
String basicAuth = "Basic " + javax.xml.bind.DatatypeConverter.printBase64Binary(userpass.getBytes());

uc.setRequestProperty ("Authorization", basicAuth);
InputStream in = uc.getInputStream();

Answer 4

If you are using the normal login whilst entering the username and password between the protocol and the domain this is simpler. It also works with and without login.

Sample Url: http://user:pass@domain.com/url

URL url = new URL("http://user:pass@domain.com/url");
URLConnection urlConnection = url.openConnection();

if (url.getUserInfo() != null) {
    String basicAuth = "Basic " + new String(new Base64().encode(url.getUserInfo().getBytes()));
    urlConnection.setRequestProperty("Authorization", basicAuth);
}

InputStream inputStream = urlConnection.getInputStream();

Please note in the comment, from valerybodak, below how it is done in an Android development environment.

Answer 5

As i have came here looking for an Android-Java-Answer i am going to do a short summary:

1. Use java.net.Authenticator as shown by James van Huis
2. Use Apache Commons HTTP Client, as in this Answer
3. Use basic java.net.URLConnection and set the Authentication-Header manually like shown here

If you want to use java.net.URLConnection with Basic Authentication in Android try this code:

URL url = new URL("http://www.mywebsite.com/resource");
URLConnection urlConnection = url.openConnection();
String header = "Basic " + new String(android.util.Base64.encode("user:pass".getBytes(), android.util.Base64.NO_WRAP));
urlConnection.addRequestProperty("Authorization", header);
// go on setting more request headers, reading the response, etc

Answer 6

Was able to set the auth using the HttpsURLConnection

           URL myUrl = new URL(httpsURL);
            HttpsURLConnection conn = (HttpsURLConnection)myUrl.openConnection();
            String userpass = username + ":" + password;
            String basicAuth = "Basic " + new String(Base64.getEncoder().encode(userpass.getBytes()));
            //httpsurlconnection
            conn.setRequestProperty("Authorization", basicAuth);

few of the changes fetched from this post. and Base64 is from java.util package.

Answer 7

Be really careful with the "Base64().encode()"approach, my team and I got 400 Apache bad request issues because it adds a \r\n at the end of the string generated.

We found it sniffing packets thanks to Wireshark.

Here is our solution :

import org.apache.commons.codec.binary.Base64;

HttpGet getRequest = new HttpGet(endpoint);
getRequest.addHeader("Authorization", "Basic " + getBasicAuthenticationEncoding());

private String getBasicAuthenticationEncoding() {

        String userPassword = username + ":" + password;
        return new String(Base64.encodeBase64(userPassword.getBytes()));
    }

Hope it helps!

Answer 8

Use this code for basic authentication.

URL url = new URL(path);
String userPass = "username:password";
String basicAuth = "Basic " + Base64.encodeToString(userPass.getBytes(), Base64.DEFAULT);//or
//String basicAuth = "Basic " + new String(Base64.encode(userPass.getBytes(), Base64.No_WRAP));
HttpURLConnection urlConnection = (HttpURLConnection)url.openConnection();
urlConnection.setRequestProperty("Authorization", basicAuth);
urlConnection.connect();

Answer 9

I'd like to provide an answer for the case that you do not have control over the code that opens the connection. Like I did when using the URLClassLoader to load a jar file from a password protected server.

The Authenticator solution would work but has the drawback that it first tries to reach the server without a password and only after the server asks for a password provides one. That's an unnecessary roundtrip if you already know the server would need a password.

public class MyStreamHandlerFactory implements URLStreamHandlerFactory {

    private final ServerInfo serverInfo;

    public MyStreamHandlerFactory(ServerInfo serverInfo) {
        this.serverInfo = serverInfo;
    }

    @Override
    public URLStreamHandler createURLStreamHandler(String protocol) {
        switch (protocol) {
            case "my":
                return new MyStreamHandler(serverInfo);
            default:
                return null;
        }
    }

}

public class MyStreamHandler extends URLStreamHandler {

    private final String encodedCredentials;

    public MyStreamHandler(ServerInfo serverInfo) {
        String strCredentials = serverInfo.getUsername() + ":" + serverInfo.getPassword();
        this.encodedCredentials = Base64.getEncoder().encodeToString(strCredentials.getBytes());
    }

    @Override
    protected URLConnection openConnection(URL url) throws IOException {
        String authority = url.getAuthority();
        String protocol = "http";
        URL directUrl = new URL(protocol, url.getHost(), url.getPort(), url.getFile());

        HttpURLConnection connection = (HttpURLConnection) directUrl.openConnection();
        connection.setRequestProperty("Authorization", "Basic " + encodedCredentials);

        return connection;
    }

}

This registers a new protocol my that is replaced by http when credentials are added. So when creating the new URLClassLoader just replace http with my and everything is fine. I know URLClassLoader provides a constructor that takes an URLStreamHandlerFactory but this factory is not used if the URL points to a jar file.

Answer 10

Since Java 9, you can do this

URL url = new URL("http://www.example.com");
HttpURLConnection connection = (HttpURLConnection)url.openConnection();
connection.setAuthenticator(new Authenticator() {
    protected PasswordAuthentication getPasswordAuthentication() {
        return new PasswordAuthentication ("USER", "PASS".toCharArray());
    }
});

Answer 11

ANDROD IMPLEMENTATION A complete method to request data/string response from web service requesting authorization with username and password

public static String getData(String uri, String userName, String userPassword) {
        BufferedReader reader = null;
        byte[] loginBytes = (userName + ":" + userPassword).getBytes();

        StringBuilder loginBuilder = new StringBuilder()
                .append("Basic ")
                .append(Base64.encodeToString(loginBytes, Base64.DEFAULT));

        try {
            URL url = new URL(uri);
            HttpURLConnection connection = (HttpURLConnection) url.openConnection();
            connection.addRequestProperty("Authorization", loginBuilder.toString());

            StringBuilder sb = new StringBuilder();
            reader = new BufferedReader(new InputStreamReader(connection.getInputStream()));
            String line;
            while ((line = reader.readLine())!= null){
                sb.append(line);
                sb.append("\n");
            }

            return  sb.toString();

        } catch (Exception e) {
            e.printStackTrace();
            return null;
        } finally {
            if (null != reader){
                try {
                    reader.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }

Answer 12

i did that this way you need to do this just copy paste it be happy

    HttpURLConnection urlConnection;
    String url;
 //   String data = json;
    String result = null;
    try {
        String username ="danish.hussain@gmail.com";
        String password = "12345678";

        String auth =new String(username + ":" + password);
        byte[] data1 = auth.getBytes(UTF_8);
        String base64 = Base64.encodeToString(data1, Base64.NO_WRAP);
        //Connect
        urlConnection = (HttpURLConnection) ((new URL(urlBasePath).openConnection()));
        urlConnection.setDoOutput(true);
        urlConnection.setRequestProperty("Content-Type", "application/json");
        urlConnection.setRequestProperty("Authorization", "Basic "+base64);
        urlConnection.setRequestProperty("Accept", "application/json");
        urlConnection.setRequestMethod("POST");
        urlConnection.setConnectTimeout(10000);
        urlConnection.connect();
        JSONObject obj = new JSONObject();

        obj.put("MobileNumber", "+97333746934");
        obj.put("EmailAddress", "danish.hussain@mee.com");
        obj.put("FirstName", "Danish");
        obj.put("LastName", "Hussain");
        obj.put("Country", "BH");
        obj.put("Language", "EN");
        String data = obj.toString();
        //Write
        OutputStream outputStream = urlConnection.getOutputStream();
        BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(outputStream, "UTF-8"));
        writer.write(data);
        writer.close();
        outputStream.close();
        int responseCode=urlConnection.getResponseCode();
        if (responseCode == HttpsURLConnection.HTTP_OK) {
            //Read
        BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(urlConnection.getInputStream(), "UTF-8"));

        String line = null;
        StringBuilder sb = new StringBuilder();

        while ((line = bufferedReader.readLine()) != null) {
            sb.append(line);
        }

        bufferedReader.close();
        result = sb.toString();

        }else {
        //    return new String("false : "+responseCode);
        new String("false : "+responseCode);
        }

    } catch (UnsupportedEncodingException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    } catch (JSONException e) {
        e.printStackTrace();
    }