Visibility.java   [plain text]

/* java.beans.Visibility
   Copyright (C) 1998, 1999 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
the Free Software Foundation; either version 2, or (at your option)
any later version.
 
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WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
General Public License for more details.

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along with GNU Classpath; see the file COPYING.  If not, write to the
Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
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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As a special exception, the copyright holders of this library give you
permission to link this library with independent modules to produce an
executable, regardless of the license terms of these independent
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independent module, the terms and conditions of the license of that
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this exception to your version of the library, but you are not
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exception statement from your version. */


package java.beans;

/**
 * Visibility is an interface a Bean may implement so that the environment
 * can tell the Bean whether there is a GUI or not, and so that the Bean
 * can tell the environment whether it needs one or can run without one.
 * <P>
 *
 * Sun decided not to use standard Introspection patterns so that these
 * methods did not get included when the Introspector made its sweep on
 * the class.
 *
 * @author John Keiser
 * @since JDK1.1
 * @version 1.1.0, 29 Jul 1998
 */

public interface Visibility {
	/**
	 * Tells whether the Bean can run without a GUI or not.
	 * @return false if Bean can run without a GUI, else true.
	 */
	public abstract boolean needsGui();

	/**
	 * Tells whether Bean is trying not to use the GUI.
	 * If needsGui() is true, this method should always return false.
	 * @return true if definitely not using GUI, otherwise false.
	 */
	public abstract boolean avoidingGui();

	/**
	 * Tells the Bean not to use GUI methods.
	 * If needsGUI() is false, then after this method is called,
	 * avoidingGui() should return true.
	 */
	public abstract void dontUseGui();

	/**
	 * Tells the Bean it may use the GUI.
	 * The Bean is not required to use the GUI in this case, it is
	 * merely being <EM>permitted</EM> to use it.  If needsGui() is
	 * false, avoidingGui() may return true or false after this method
	 * is called.
	 */
	public abstract void okToUseGui();
}