Source code: com/paradoxpoint/libitina/util/ExampleFileFilter.java
1 /*
2 * Copyright (c) 2003 Sun Microsystems, Inc. All Rights Reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 *
8 * -Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 *
11 * -Redistribution in binary form must reproduct the above copyright
12 * notice, this list of conditions and the following disclaimer in
13 * the documentation and/or other materials provided with the distribution.
14 *
15 * Neither the name of Sun Microsystems, Inc. or the names of contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * This software is provided "AS IS," without a warranty of any kind. ALL
20 * EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES, INCLUDING
21 * ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE
22 * OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN AND ITS LICENSORS SHALL NOT
23 * BE LIABLE FOR ANY DAMAGES OR LIABILITIES SUFFERED BY LICENSEE AS A RESULT
24 * OF OR RELATING TO USE, MODIFICATION OR DISTRIBUTION OF THE SOFTWARE OR ITS
25 * DERIVATIVES. IN NO EVENT WILL SUN OR ITS LICENSORS BE LIABLE FOR ANY LOST
26 * REVENUE, PROFIT OR DATA, OR FOR DIRECT, INDIRECT, SPECIAL, CONSEQUENTIAL,
27 * INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER CAUSED AND REGARDLESS OF THE THEORY
28 * OF LIABILITY, ARISING OUT OF THE USE OF OR INABILITY TO USE SOFTWARE, EVEN
29 * IF SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
30 *
31 * You acknowledge that Software is not designed, licensed or intended for
32 * use in the design, construction, operation or maintenance of any nuclear
33 * facility.
34 */
35
36 /*
37 * @(#)ExampleFileFilter.java 1.14 03/01/23
38 */
39
40
41 package com.paradoxpoint.libitina.util;
42
43 import java.io.File;
44 import java.util.Hashtable;
45 import java.util.Enumeration;
46 import javax.swing.*;
47 import javax.swing.filechooser.*;
48
49 /**
50 * A convenience implementation of FileFilter that filters out
51 * all files except for those type extensions that it knows about.
52 *
53 * Extensions are of the type ".foo", which is typically found on
54 * Windows and Unix boxes, but not on Macinthosh. Case is ignored.
55 *
56 * Example - create a new filter that filerts out all files
57 * but gif and jpg image files:
58 *
59 * JFileChooser chooser = new JFileChooser();
60 * ExampleFileFilter filter = new ExampleFileFilter(
61 * new String{"gif", "jpg"}, "JPEG & GIF Images")
62 * chooser.addChoosableFileFilter(filter);
63 * chooser.showOpenDialog(this);
64 *
65 * @version 1.14 01/23/03
66 * @author Jeff Dinkins
67 */
68 public class ExampleFileFilter extends FileFilter {
69
70 private static String TYPE_UNKNOWN = "Type Unknown";
71 private static String HIDDEN_FILE = "Hidden File";
72
73 private Hashtable filters = null;
74 private String description = null;
75 private String fullDescription = null;
76 private boolean useExtensionsInDescription = true;
77
78 /**
79 * Creates a file filter. If no filters are added, then all
80 * files are accepted.
81 *
82 * @see #addExtension
83 */
84 public ExampleFileFilter() {
85 this.filters = new Hashtable();
86 }
87
88 /**
89 * Creates a file filter that accepts files with the given extension.
90 * Example: new ExampleFileFilter("jpg");
91 *
92 * @see #addExtension
93 */
94 public ExampleFileFilter(String extension) {
95 this(extension,null);
96 }
97
98 /**
99 * Creates a file filter that accepts the given file type.
100 * Example: new ExampleFileFilter("jpg", "JPEG Image Images");
101 *
102 * Note that the "." before the extension is not needed. If
103 * provided, it will be ignored.
104 *
105 * @see #addExtension
106 */
107 public ExampleFileFilter(String extension, String description) {
108 this();
109 if(extension!=null) addExtension(extension);
110 if(description!=null) setDescription(description);
111 }
112
113 /**
114 * Creates a file filter from the given string array.
115 * Example: new ExampleFileFilter(String {"gif", "jpg"});
116 *
117 * Note that the "." before the extension is not needed adn
118 * will be ignored.
119 *
120 * @see #addExtension
121 */
122 public ExampleFileFilter(String[] filters) {
123 this(filters, null);
124 }
125
126 /**
127 * Creates a file filter from the given string array and description.
128 * Example: new ExampleFileFilter(String {"gif", "jpg"}, "Gif and JPG Images");
129 *
130 * Note that the "." before the extension is not needed and will be ignored.
131 *
132 * @see #addExtension
133 */
134 public ExampleFileFilter(String[] filters, String description) {
135 this();
136 for (int i = 0; i < filters.length; i++) {
137 // add filters one by one
138 addExtension(filters[i]);
139 }
140 if(description!=null) setDescription(description);
141 }
142
143 /**
144 * Return true if this file should be shown in the directory pane,
145 * false if it shouldn't.
146 *
147 * Files that begin with "." are ignored.
148 *
149 * @see #getExtension
150 * @see FileFilter#accepts
151 */
152 public boolean accept(File f) {
153 if(f != null) {
154 if(f.isDirectory()) {
155 return true;
156 }
157 String extension = getExtension(f);
158 if(extension != null && filters.get(getExtension(f)) != null) {
159 return true;
160 };
161 }
162 return false;
163 }
164
165 /**
166 * Return the extension portion of the file's name .
167 *
168 * @see #getExtension
169 * @see FileFilter#accept
170 */
171 public String getExtension(File f) {
172 if(f != null) {
173 String filename = f.getName();
174 int i = filename.lastIndexOf('.');
175 if(i>0 && i<filename.length()-1) {
176 return filename.substring(i+1).toLowerCase();
177 };
178 }
179 return null;
180 }
181
182 /**
183 * Adds a filetype "dot" extension to filter against.
184 *
185 * For example: the following code will create a filter that filters
186 * out all files except those that end in ".jpg" and ".tif":
187 *
188 * ExampleFileFilter filter = new ExampleFileFilter();
189 * filter.addExtension("jpg");
190 * filter.addExtension("tif");
191 *
192 * Note that the "." before the extension is not needed and will be ignored.
193 */
194 public void addExtension(String extension) {
195 if(filters == null) {
196 filters = new Hashtable(5);
197 }
198 filters.put(extension.toLowerCase(), this);
199 fullDescription = null;
200 }
201
202
203 /**
204 * Returns the human readable description of this filter. For
205 * example: "JPEG and GIF Image Files (*.jpg, *.gif)"
206 *
207 * @see setDescription
208 * @see setExtensionListInDescription
209 * @see isExtensionListInDescription
210 * @see FileFilter#getDescription
211 */
212 public String getDescription() {
213 if(fullDescription == null) {
214 if(description == null || isExtensionListInDescription()) {
215 fullDescription = description==null ? "(" : description + " (";
216 // build the description from the extension list
217 Enumeration extensions = filters.keys();
218 if(extensions != null) {
219 fullDescription += "." + (String) extensions.nextElement();
220 while (extensions.hasMoreElements()) {
221 fullDescription += ", ." + (String) extensions.nextElement();
222 }
223 }
224 fullDescription += ")";
225 } else {
226 fullDescription = description;
227 }
228 }
229 return fullDescription;
230 }
231
232 /**
233 * Sets the human readable description of this filter. For
234 * example: filter.setDescription("Gif and JPG Images");
235 *
236 * @see setDescription
237 * @see setExtensionListInDescription
238 * @see isExtensionListInDescription
239 */
240 public void setDescription(String description) {
241 this.description = description;
242 fullDescription = null;
243 }
244
245 /**
246 * Determines whether the extension list (.jpg, .gif, etc) should
247 * show up in the human readable description.
248 *
249 * Only relevent if a description was provided in the constructor
250 * or using setDescription();
251 *
252 * @see getDescription
253 * @see setDescription
254 * @see isExtensionListInDescription
255 */
256 public void setExtensionListInDescription(boolean b) {
257 useExtensionsInDescription = b;
258 fullDescription = null;
259 }
260
261 /**
262 * Returns whether the extension list (.jpg, .gif, etc) should
263 * show up in the human readable description.
264 *
265 * Only relevent if a description was provided in the constructor
266 * or using setDescription();
267 *
268 * @see getDescription
269 * @see setDescription
270 * @see setExtensionListInDescription
271 */
272 public boolean isExtensionListInDescription() {
273 return useExtensionsInDescription;
274 }
275 }