001 /* java.beans.Visibility
002 Copyright (C) 1998, 1999 Free Software Foundation, Inc.
003
004 This file is part of GNU Classpath.
005
006 GNU Classpath is free software; you can redistribute it and/or modify
007 it under the terms of the GNU General Public License as published by
008 the Free Software Foundation; either version 2, or (at your option)
009 any later version.
010
011 GNU Classpath is distributed in the hope that it will be useful, but
012 WITHOUT ANY WARRANTY; without even the implied warranty of
013 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
014 General Public License for more details.
015
016 You should have received a copy of the GNU General Public License
017 along with GNU Classpath; see the file COPYING. If not, write to the
018 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
019 02110-1301 USA.
020
021 Linking this library statically or dynamically with other modules is
022 making a combined work based on this library. Thus, the terms and
023 conditions of the GNU General Public License cover the whole
024 combination.
025
026 As a special exception, the copyright holders of this library give you
027 permission to link this library with independent modules to produce an
028 executable, regardless of the license terms of these independent
029 modules, and to copy and distribute the resulting executable under
030 terms of your choice, provided that you also meet, for each linked
031 independent module, the terms and conditions of the license of that
032 module. An independent module is a module which is not derived from
033 or based on this library. If you modify this library, you may extend
034 this exception to your version of the library, but you are not
035 obligated to do so. If you do not wish to do so, delete this
036 exception statement from your version. */
037
038
039 package java.beans;
040
041 /**
042 * Visibility is an interface a Bean may implement so that the environment
043 * can tell the Bean whether there is a GUI or not, and so that the Bean
044 * can tell the environment whether it needs one or can run without one.
045 * <P>
046 *
047 * Sun decided not to use standard Introspection patterns so that these
048 * methods did not get included when the Introspector made its sweep on
049 * the class.
050 *
051 * @author John Keiser
052 * @since JDK1.1
053 * @version 1.1.0, 29 Jul 1998
054 */
055
056 public interface Visibility {
057 /**
058 * Tells whether the Bean can run without a GUI or not.
059 * @return false if Bean can run without a GUI, else true.
060 */
061 boolean needsGui();
062
063 /**
064 * Tells whether Bean is trying not to use the GUI.
065 * If needsGui() is true, this method should always return false.
066 * @return true if definitely not using GUI, otherwise false.
067 */
068 boolean avoidingGui();
069
070 /**
071 * Tells the Bean not to use GUI methods.
072 * If needsGUI() is false, then after this method is called,
073 * avoidingGui() should return true.
074 */
075 void dontUseGui();
076
077 /**
078 * Tells the Bean it may use the GUI.
079 * The Bean is not required to use the GUI in this case, it is
080 * merely being <EM>permitted</EM> to use it. If needsGui() is
081 * false, avoidingGui() may return true or false after this method
082 * is called.
083 */
084 void okToUseGui();
085 }