001    /*
002     * Copyright 2002-2004 the original author or authors.
003     * 
004     * Licensed under the Apache License, Version 2.0 (the "License"); you may not
005     * use this file except in compliance with the License. You may obtain a copy of
006     * the License at
007     * 
008     * http://www.apache.org/licenses/LICENSE-2.0
009     * 
010     * Unless required by applicable law or agreed to in writing, software
011     * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
012     * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
013     * License for the specific language governing permissions and limitations under
014     * the License.
015     */
016    package org.springframework.richclient.command.support;
017    
018    import java.beans.PropertyChangeEvent;
019    import java.beans.PropertyChangeListener;
020    import java.lang.ref.WeakReference;
021    import java.util.HashSet;
022    import java.util.Iterator;
023    import java.util.NoSuchElementException;
024    import java.util.Set;
025    
026    import javax.swing.AbstractButton;
027    
028    import org.springframework.core.style.ToStringCreator;
029    import org.springframework.richclient.command.AbstractCommand;
030    import org.springframework.richclient.command.config.CommandButtonConfigurer;
031    import org.springframework.richclient.command.config.CommandFaceDescriptor;
032    import org.springframework.util.Assert;
033    import org.springframework.util.ObjectUtils;
034    
035    public class CommandFaceButtonManager implements PropertyChangeListener {
036        private Set buttons = new HashSet(6);
037    
038        private AbstractCommand command;
039    
040        private String faceDescriptorId;
041    
042        private CommandFaceDescriptor faceDescriptor;
043    
044        private static class ManagedButton {
045            private WeakReference buttonHolder;
046    
047            private CommandButtonConfigurer buttonConfigurer;
048            
049            private int hashCode;
050    
051            public ManagedButton(AbstractButton button, CommandButtonConfigurer buttonConfigurer) {
052                this.buttonHolder = new WeakReference(button);
053                this.buttonConfigurer = buttonConfigurer;
054                this.hashCode = button.hashCode();
055            }
056    
057            public AbstractButton getButton() {
058                return (AbstractButton)buttonHolder.get();
059            }
060    
061            public boolean equals(Object o) {
062                    if (o == null) {
063                            return false;
064                    }
065                if (this == o) {
066                    return true;
067                }
068                return ObjectUtils.nullSafeEquals(getButton(), ((ManagedButton)o).getButton());
069            }
070    
071            public int hashCode() {
072                return hashCode;
073            }
074        }
075    
076        public CommandFaceButtonManager(AbstractCommand command, String faceDescriptorKey) {
077            Assert.notNull(command, "The command to manage buttons for cannot be null");
078            Assert.hasText(faceDescriptorKey, "The face descriptor key is required");
079            this.command = command;
080            this.faceDescriptorId = faceDescriptorKey;
081        }
082    
083        public CommandFaceButtonManager(AbstractCommand command, CommandFaceDescriptor faceDescriptor) {
084            this.command = command;
085            setFaceDescriptor(faceDescriptor);
086        }
087    
088        public void setFaceDescriptor(CommandFaceDescriptor faceDescriptor) {
089            Assert.notNull(faceDescriptor, "The face descriptor for managing command button appearance is required");
090            if (!ObjectUtils.nullSafeEquals(this.faceDescriptor, faceDescriptor)) {
091                if (this.faceDescriptor != null) {
092                    this.faceDescriptor.removePropertyChangeListener(this);
093                }
094                this.faceDescriptor = faceDescriptor;
095                this.faceDescriptor.addPropertyChangeListener(this);
096                propertyChange(null);
097            }
098        }
099    
100        public CommandFaceDescriptor getFaceDescriptor() {
101            return faceDescriptor;
102        }
103    
104        public boolean isFaceConfigured() {
105            return this.faceDescriptor != null;
106        }
107    
108        public void attachAndConfigure(AbstractButton button, CommandButtonConfigurer strategy) {
109            Assert.notNull(button, "The button to attach and configure is required");
110            Assert.notNull(strategy, "The button configuration strategy is required");
111            if (!isAttachedTo(button)) {
112                ManagedButton managedButton = new ManagedButton(button, strategy);
113                if (buttons.add(managedButton)) {
114                    configure(button, strategy);
115                }
116            }
117        }
118    
119        private void cleanUp() {
120            for (Iterator i = buttons.iterator(); i.hasNext();) {
121                ManagedButton button = (ManagedButton)i.next();
122                if (button.getButton() == null) {
123                    i.remove();
124                }
125            }
126        }
127    
128        protected void configure(AbstractButton button, CommandButtonConfigurer strategy) {
129            if (this.faceDescriptor == null) {
130                if (command.getFaceDescriptorRegistry() != null) {
131                    setFaceDescriptor(command.getFaceDescriptorRegistry().getFaceDescriptor(command, faceDescriptorId));
132                } else {
133                    setFaceDescriptor(new CommandFaceDescriptor());
134                }
135            }
136    
137            getFaceDescriptor().configure(button, command, strategy);
138        }
139    
140        public void detach(AbstractButton button) {
141            buttons.remove(findManagedButton(button));
142        }
143    
144        public void detachAll() {
145            buttons.clear();
146        }
147    
148        public boolean isAttachedTo(AbstractButton button) {
149            return findManagedButton(button) != null;
150        }
151    
152        protected ManagedButton findManagedButton(AbstractButton button) {
153            Assert.notNull(button, "The button is required");
154            cleanUp();
155            for (Iterator i = buttons.iterator(); i.hasNext();) {
156                ManagedButton managedButton = (ManagedButton)i.next();
157                if (button.equals(managedButton.getButton())) {
158                    return managedButton;
159                }
160            }
161            return null;
162        }
163    
164        public Iterator iterator() {
165            cleanUp();
166            return new ButtonIterator(buttons.iterator());
167        }
168    
169        private static class ButtonIterator implements Iterator {
170            private Iterator it;
171    
172            private AbstractButton nextButton;
173    
174            public ButtonIterator(Iterator it) {
175                this.it = it;
176                fetchNextButton();
177            }
178    
179            public boolean hasNext() {
180                return nextButton != null;
181            }
182    
183            public Object next() {
184                if (nextButton == null) {
185                    throw new NoSuchElementException();
186                }
187                AbstractButton lastButton = nextButton;
188                fetchNextButton();
189                return lastButton;
190            }
191    
192            public void remove() {
193                throw new UnsupportedOperationException();
194            }
195    
196            private void fetchNextButton() {
197                while (it.hasNext()) {
198                    ManagedButton managedButton = (ManagedButton)it.next();
199                    nextButton = managedButton.getButton();
200                    if (nextButton != null) {
201                        return;
202                    }
203                }
204                nextButton = null;
205            }
206        }
207    
208        public void propertyChange(PropertyChangeEvent e) {
209            Iterator it = buttons.iterator();
210            while (it.hasNext()) {
211                ManagedButton mb = (ManagedButton)it.next();
212                Assert.notNull(mb, "Managed button reference cannot be null");
213                if (mb.getButton() == null) {
214                    it.remove();
215                }
216                else {
217                    configure(mb.getButton(), mb.buttonConfigurer);
218                }
219            }
220        }
221    
222        public String toString() {
223            return new ToStringCreator(this).append("commandId", command.getId())
224                    .append("faceDescriptor", faceDescriptor)
225                    .append("attachedButtonCount", buttons.size())
226                    .toString();
227        }
228    }