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1   package org.apache.turbine.util;
2   
3   /*
4    * Copyright 2001-2005 The Apache Software Foundation.
5    *
6    * Licensed under the Apache License, Version 2.0 (the "License")
7    * you may not use this file except in compliance with the License.
8    * You may obtain a copy of the License at
9    *
10   *     http://www.apache.org/licenses/LICENSE-2.0
11   *
12   * Unless required by applicable law or agreed to in writing, software
13   * distributed under the License is distributed on an "AS IS" BASIS,
14   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15   * See the License for the specific language governing permissions and
16   * limitations under the License.
17   */
18  
19  /***
20   * This class parses the user agent string and sets javasciptOK and
21   * cssOK following the rules described below.  If you want to check
22   * for specific browsers/versions then use this class to parse the
23   * user agent string and use the accessor methods in this class.
24   *
25   * JavaScriptOK means that the browser understands JavaScript on the
26   * same level the Navigator 3 does.  Specifically, it can use named
27   * images.  This allows easier rollovers.  If a browser doesn't do
28   * this (Nav 2 or MSIE 3), then we just assume it can't do any
29   * JavaScript.  Referencing images by load order is too hard to
30   * maintain.
31   *
32   * CSSOK is kind of sketchy in that Nav 4 and MSIE work differently,
33   * but they do seem to have most of the functionality.  MSIE 4 for the
34   * Mac has buggy CSS support, so we let it do JavaScript, but no CSS.
35   *
36   * Ported from Leon's PHP code at
37   * http://www.working-dogs.com/freetrade by Frank.
38   *
39   * @author <a href="mailto:frank.kim@clearink.com">Frank Y. Kim</a>
40   * @author <a href="mailto:leon@clearink.com">Leon Atkisnon</a>
41   * @author <a href="mailto:mospaw@polk-county.com">Chris Mospaw</a>
42   * @author <a href="mailto:bgriffin@cddb.com">Benjamin Elijah Griffin</a>
43   * @version $Id: BrowserDetector.java 264152 2005-08-29 14:50:22Z henning $
44   */
45  public class BrowserDetector
46  {
47      public static final String MSIE = "MSIE";
48      public static final String OPERA = "Opera";
49      public static final String MOZILLA = "Mozilla";
50  
51      public static final String WINDOWS = "Windows";
52      public static final String UNIX = "Unix";
53      public static final String MACINTOSH = "Macintosh";
54  
55      /*** The user agent string. */
56      private String userAgentString = "";
57  
58      /*** The browser name specified in the user agent string. */
59      private String browserName = "";
60  
61      /***
62       * The browser version specified in the user agent string.  If we
63       * can't parse the version just assume an old browser.
64       */
65      private float browserVersion = (float) 1.0;
66  
67      /***
68       * The browser platform specified in the user agent string.
69       */
70      private String browserPlatform = "unknown";
71  
72      /*** Whether or not javascript works in this browser. */
73      private boolean javascriptOK = false;
74  
75      /*** Whether or not CSS works in this browser. */
76      private boolean cssOK = false;
77  
78      /*** Whether or not file upload works in this browser. */
79      private boolean fileUploadOK = false;
80  
81      /***
82       * Constructor used to initialize this class.
83       *
84       * @param userAgentString A String with the user agent field.
85       */
86      public BrowserDetector(String userAgentString)
87      {
88          this.userAgentString = userAgentString;
89          parse();
90      }
91  
92      /***
93       * Constructor used to initialize this class.
94       *
95       * @param data The Turbine RunData object.
96       */
97      public BrowserDetector(RunData data)
98      {
99          this.userAgentString = data.getUserAgent();
100         parse();
101     }
102 
103     /***
104      * Whether or not CSS works in this browser.
105      *
106      * @return True if CSS works in this browser.
107      */
108     public boolean isCssOK()
109     {
110         return cssOK;
111     }
112 
113     /***
114      * Whether or not file upload works in this browser.
115      *
116      * @return True if file upload works in this browser.
117      */
118     public boolean isFileUploadOK()
119     {
120         return fileUploadOK;
121     }
122 
123     /***
124      * Whether or not Javascript works in this browser.
125      *
126      * @return True if Javascript works in this browser.
127      */
128     public boolean isJavascriptOK()
129     {
130         return javascriptOK;
131     }
132 
133     /***
134      * The browser name specified in the user agent string.
135      *
136      * @return A String with the browser name.
137      */
138     public String getBrowserName()
139     {
140         return browserName;
141     }
142 
143     /***
144      * The browser platform specified in the user agent string.
145      *
146      * @return A String with the browser platform.
147      */
148     public String getBrowserPlatform()
149     {
150         return browserPlatform;
151     }
152 
153     /***
154      * The browser version specified in the user agent string.
155      *
156      * @return A String with the browser version.
157      */
158     public float getBrowserVersion()
159     {
160         return browserVersion;
161     }
162 
163     /***
164      * The user agent string for this class.
165      *
166      * @return A String with the user agent.
167      */
168     public String getUserAgentString()
169     {
170         return userAgentString;
171     }
172 
173     /***
174      * Helper method to initialize this class.
175      */
176     private void parse()
177     {
178         int versionStartIndex = userAgentString.indexOf("/");
179         int versionEndIndex = userAgentString.indexOf(" ");
180 
181         // Get the browser name and version.
182         browserName = userAgentString.substring(0, versionStartIndex);
183         try
184         {
185             // Not all user agents will have a space in the reported
186             // string.
187             String agentSubstring = null;
188             if (versionEndIndex < 0)
189             {
190                 agentSubstring
191                         = userAgentString.substring(versionStartIndex + 1);
192             }
193             else
194             {
195                 agentSubstring = userAgentString
196                         .substring(versionStartIndex + 1, versionEndIndex);
197             }
198             browserVersion = toFloat(agentSubstring);
199         }
200         catch (NumberFormatException e)
201         {
202             // Just use the default value.
203         }
204 
205         // MSIE lies about its name.  Of course...
206         if (userAgentString.indexOf(MSIE) != -1)
207         {
208             // Ex: Mozilla/4.0 (compatible; MSIE 5.0; Windows NT; DigExt)
209             versionStartIndex = (userAgentString.indexOf(MSIE)
210                     + MSIE.length() + 1);
211             versionEndIndex = userAgentString.indexOf(";", versionStartIndex);
212 
213             browserName = MSIE;
214             try
215             {
216                 browserVersion = toFloat(userAgentString
217                         .substring(versionStartIndex, versionEndIndex));
218             }
219             catch (NumberFormatException e)
220             {
221                 // Just use the default value.
222             }
223 
224             // PHP code
225             // $Browser_Name = "MSIE";
226             // $Browser_Version = strtok("MSIE");
227             // $Browser_Version = strtok(" ");
228             // $Browser_Version = strtok(";");
229         }
230 
231         // Opera isn't completely honest, either...
232         // Modificaton by Chris Mospaw <mospaw@polk-county.com>
233         if (userAgentString.indexOf(OPERA) != -1)
234         {
235             //Ex: Mozilla/4.0 (Windows NT 4.0;US) Opera 3.61  [en]
236             versionStartIndex = (userAgentString.indexOf(OPERA)
237                     + OPERA.length() + 1);
238             versionEndIndex = userAgentString.indexOf(" ", versionStartIndex);
239 
240             browserName = OPERA;
241             try
242             {
243                 browserVersion = toFloat(userAgentString
244                         .substring(versionStartIndex, versionEndIndex));
245             }
246             catch (NumberFormatException e)
247             {
248                 // Just use the default value.
249             }
250 
251             // PHP code
252             // $Browser_Name = "Opera";
253             // $Browser_Version = strtok("Opera");
254             // $Browser_Version = strtok("/");
255             // $Browser_Version = strtok(";");
256         }
257 
258 
259         // Try to figure out what platform.
260         if ((userAgentString.indexOf("Windows") != -1)
261                 || (userAgentString.indexOf("WinNT") != -1)
262                 || (userAgentString.indexOf("Win98") != -1)
263                 || (userAgentString.indexOf("Win95") != -1))
264         {
265             browserPlatform = WINDOWS;
266         }
267 
268         if (userAgentString.indexOf("Mac") != -1)
269         {
270             browserPlatform = MACINTOSH;
271         }
272 
273         if (userAgentString.indexOf("X11") != -1)
274         {
275             browserPlatform = UNIX;
276         }
277 
278         if (browserPlatform == WINDOWS)
279         {
280             if (browserName.equals(MOZILLA))
281             {
282                 if (browserVersion >= 3.0)
283                 {
284                     javascriptOK = true;
285                     fileUploadOK = true;
286                 }
287                 if (browserVersion >= 4.0)
288                 {
289                     cssOK = true;
290                 }
291             }
292             else if (browserName == MSIE)
293             {
294                 if (browserVersion >= 4.0)
295                 {
296                     javascriptOK = true;
297                     fileUploadOK = true;
298                     cssOK = true;
299                 }
300             }
301             else if (browserName == OPERA)
302             {
303                 if (browserVersion >= 3.0)
304                 {
305                     javascriptOK = true;
306                     fileUploadOK = true;
307                     cssOK = true;
308                 }
309             }
310         }
311         else if (browserPlatform == MACINTOSH)
312         {
313             if (browserName.equals(MOZILLA))
314             {
315                 if (browserVersion >= 3.0)
316                 {
317                     javascriptOK = true;
318                     fileUploadOK = true;
319                 }
320                 if (browserVersion >= 4.0)
321                 {
322                     cssOK = true;
323                 }
324             }
325             else if (browserName == MSIE)
326             {
327                 if (browserVersion >= 4.0)
328                 {
329                     javascriptOK = true;
330                     fileUploadOK = true;
331                 }
332                 if (browserVersion > 4.0)
333                 {
334                     cssOK = true;
335                 }
336             }
337         }
338         else if (browserPlatform == UNIX)
339         {
340             if (browserName.equals(MOZILLA))
341             {
342                 if (browserVersion >= 3.0)
343                 {
344                     javascriptOK = true;
345                     fileUploadOK = true;
346                 }
347                 if (browserVersion >= 4.0)
348                 {
349                     cssOK = true;
350                 }
351             }
352         }
353     }
354 
355     /***
356      * Helper method to convert String to a float.
357      *
358      * @param s A String.
359      * @return The String converted to float.
360      */
361     private static float toFloat(String s)
362     {
363         return Float.valueOf(s).floatValue();
364     }
365 
366 }