/* Callback.java -- marker interface for callback classes
   Copyright (C) 2003, 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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02110-1301 USA.

Linking this library statically or dynamically with other modules is
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permission to link this library with independent modules to produce an
executable, regardless of the license terms of these independent
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this exception to your version of the library, but you are not
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package javax.security.auth.callback;

/**
 * <p>Implementations of this interface are passed to a {@link CallbackHandler},
 * allowing underlying security services the ability to interact with a calling
 * application to retrieve specific authentication data such as usernames and
 * passwords, or to display certain information, such as error and warning
 * messages.</p>
 *
 * <p><code>Callback</code> implementations do not retrieve or display the
 * information requested by underlying security services. <code>Callback</code>
 * implementations simply provide the means to pass such requests to
 * applications, and for applications, if appropriate, to return requested
 * information back to the underlying security services.</p>
 *
 * @see CallbackHandler
 * @see ChoiceCallback
 * @see ConfirmationCallback
 * @see LanguageCallback
 * @see NameCallback
 * @see PasswordCallback
 * @see TextInputCallback
 * @see TextOutputCallback
 */
public interface Callback {
}