public class BasicAuth {

    private String user;
    private String pass;

    public BasicAuth(String user, String pass) {

        if (TextUtils.isEmpty(user)) {
            throw new IllegalArgumentException("user cannot be null");
        }

        if (TextUtils.isEmpty(pass)) {
            throw new IllegalArgumentException("pass cannot be null");
        }

        this.user = user;
        this.pass = pass;
    }

    public String getHeaderValue() {
        byte[] bytes = String.format("%s:%s", user, pass).getBytes();
        String value = String.format("Basic %s", Base64.encodeToString(bytes, Base64.DEFAULT));
        return value.trim();
    }

    public String getHeaderName() {
        return "Authorization";
    }

}