001    /* ========================================================================
002     * JCommon : a free general purpose class library for the Java(tm) platform
003     * ========================================================================
004     *
005     * (C) Copyright 2000-2005, by Object Refinery Limited and Contributors.
006     * 
007     * Project Info:  http://www.jfree.org/jcommon/index.html
008     *
009     * This library is free software; you can redistribute it and/or modify it 
010     * under the terms of the GNU Lesser General Public License as published by 
011     * the Free Software Foundation; either version 2.1 of the License, or 
012     * (at your option) any later version.
013     *
014     * This library is distributed in the hope that it will be useful, but 
015     * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 
016     * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public 
017     * License for more details.
018     *
019     * You should have received a copy of the GNU Lesser General Public
020     * License along with this library; if not, write to the Free Software
021     * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, 
022     * USA.  
023     *
024     * [Java is a trademark or registered trademark of Sun Microsystems, Inc. 
025     * in the United States and other countries.]
026     * 
027     * ----------------
028     * WizardPanel.java
029     * ----------------
030     * (C) Copyright 2000-2004, by Object Refinery Limited.
031     *
032     * Original Author:  David Gilbert (for Object Refinery Limited);
033     * Contributor(s):   -;
034     *
035     * $Id: WizardPanel.java,v 1.4 2005/11/16 15:58:41 taqua Exp $
036     *
037     * Changes (from 26-Oct-2001)
038     * --------------------------
039     * 26-Oct-2001 : Changed package to com.jrefinery.ui.*;
040     * 14-Oct-2002 : Fixed errors reported by Checkstyle (DG);
041     *
042     */
043    
044    package org.jfree.ui;
045    
046    import java.awt.LayoutManager;
047    
048    import javax.swing.JPanel;
049    
050    /**
051     * A panel that provides the user interface for a single step in a WizardDialog.
052     *
053     * @author David Gilbert
054     */
055    public abstract class WizardPanel extends JPanel {
056    
057        /** The owner. */
058        private WizardDialog owner;
059    
060        /**
061         * Creates a new panel.
062         *
063         * @param layout  the layout manager.
064         */
065        protected WizardPanel(final LayoutManager layout) {
066            super(layout);
067        }
068    
069        /**
070         * Returns a reference to the dialog that owns the panel.
071         *
072         * @return the owner.
073         */
074        public WizardDialog getOwner() {
075            return this.owner;
076        }
077    
078        /**
079         * Sets the reference to the dialog that owns the panel (this is called automatically by
080         * the dialog when the panel is added to the dialog).
081         *
082         * @param owner  the owner.
083         */
084        public void setOwner(final WizardDialog owner) {
085            this.owner = owner;
086        }
087    
088        /**
089         * Returns the result.
090         *
091         * @return the result.
092         */
093        public Object getResult() {
094            return null;
095        }
096    
097        /**
098         * This method is called when the dialog redisplays this panel as a result of the user clicking
099         * the "Previous" button.  Inside this method, subclasses should make a note of their current
100         * state, so that they can decide what to do when the user hits "Next".
101         */
102        public abstract void returnFromLaterStep();
103    
104        /**
105         * Returns true if it is OK to redisplay the last version of the next panel, or false if a new
106         * version is required.
107         *
108         * @return boolean.
109         */
110        public abstract boolean canRedisplayNextPanel();
111    
112        /**
113         * Returns true if there is a next panel.
114         *
115         * @return boolean.
116         */
117        public abstract boolean hasNextPanel();
118    
119        /**
120         * Returns true if it is possible to finish from this panel.
121         *
122         * @return boolean.
123         */
124        public abstract boolean canFinish();
125    
126        /**
127         * Returns the next panel in the sequence, given the current user input.  Returns null if this
128         * panel is the last one in the sequence.
129         *
130         * @return the next panel in the sequence.
131         */
132        public abstract WizardPanel getNextPanel();
133    
134    }