/* Authenticator.java --
   Copyright (C) 2004 Free Software Foundation, Inc.

This file is part of GNU Classpath.

GNU Classpath is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
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02111-1307 USA.

Linking this library statically or dynamically with other modules is
making a combined work based on this library.  Thus, the terms and
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permission to link this library with independent modules to produce an
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package gnu.java.net.protocol.http;

/**
 * Callback interface for managing authentication.
 * @see Request#setAuthenticator
 *
 * @author Chris Burdess (dog@gnu.org)
 */
public interface Authenticator
{

  /**
   * Returns the credentials to supply for the given realm.
   * @param realm the authentication realm
   * @param attempt zero on first authentication attempt, increments on each
   * unsuccessful attempt
   */
  Credentials getCredentials(String realm, int attempt);
  
}