Cursor


1   /*
2    * @(#)Cursor.java  1.43 06/10/23
3    *
4    * Copyright 2004 Sun Microsystems, Inc. All rights reserved.
5    * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
6    */
7   package java.awt;
8   
9   import java.awt.AWTException  ;
10  import java.awt.Point  ;
11  import java.awt.Toolkit  ;
12  
13  import java.io.File  ;
14  import java.io.FileInputStream  ;
15  
16  import java.util.Enumeration  ;
17  import java.util.Hashtable  ;
18  import java.util.Properties  ;
19  import java.util.StringTokenizer  ;
20  
21  import java.security.AccessController  ;
22  
23  import sun.awt.DebugHelper;
24  
25  /**
26   * A class to encapsulate the bitmap representation of the mouse cursor.
27   *
28   * @see Component#setCursor
29   * @version     1.43, 10/23/06
30   * @author  Amy Fowler
31   */
32  public class Cursor implements java.io.Serializable   {
33  
34      /**
35       * The default cursor type (gets set if no cursor is defined).
36       */
37      public static final int DEFAULT_CURSOR          = 0;
38  
39      /**
40       * The crosshair cursor type.
41       */
42      public static final int CROSSHAIR_CURSOR        = 1;
43  
44      /**
45       * The text cursor type.
46       */
47      public static final int TEXT_CURSOR             = 2;
48  
49      /**
50       * The wait cursor type.
51       */
52      public static final int WAIT_CURSOR         = 3;
53  
54      /**
55       * The south-west-resize cursor type.
56       */
57      public static final int SW_RESIZE_CURSOR        = 4;
58  
59      /**
60       * The south-east-resize cursor type.
61       */
62      public static final int SE_RESIZE_CURSOR        = 5;
63  
64      /**
65       * The north-west-resize cursor type.
66       */
67      public static final int NW_RESIZE_CURSOR        = 6;
68  
69      /**
70       * The north-east-resize cursor type.
71       */
72      public static final int NE_RESIZE_CURSOR        = 7;
73  
74      /**
75       * The north-resize cursor type.
76       */
77      public static final int N_RESIZE_CURSOR         = 8;
78  
79      /**
80       * The south-resize cursor type.
81       */
82      public static final int S_RESIZE_CURSOR         = 9;
83  
84      /**
85       * The west-resize cursor type.
86       */
87      public static final int W_RESIZE_CURSOR         = 10;
88  
89      /**
90       * The east-resize cursor type.
91       */
92      public static final int E_RESIZE_CURSOR         = 11;
93  
94      /**
95       * The hand cursor type.
96       */
97      public static final int HAND_CURSOR         = 12;
98  
99      /**
100      * The move cursor type.
101      */
102     public static final int MOVE_CURSOR         = 13;
103 
104     protected static Cursor   predefined[] = new Cursor  [14];
105 
106     /* Localization names and default values */
107     static final String  [][] cursorProperties = {
108         { "AWT.DefaultCursor", "Default Cursor" },
109         { "AWT.CrosshairCursor", "Crosshair Cursor" },
110         { "AWT.TextCursor", "Text Cursor" },
111         { "AWT.WaitCursor", "Wait Cursor" },
112         { "AWT.SWResizeCursor", "Southwest Resize Cursor" },
113         { "AWT.SEResizeCursor", "Southeast Resize Cursor" },
114         { "AWT.NWResizeCursor", "Northwest Resize Cursor" },
115         { "AWT.NEResizeCursor", "Northeast Resize Cursor" },
116         { "AWT.NResizeCursor", "North Resize Cursor" },
117         { "AWT.SResizeCursor", "South Resize Cursor" },
118         { "AWT.WResizeCursor", "West Resize Cursor" },
119         { "AWT.EResizeCursor", "East Resize Cursor" },
120         { "AWT.HandCursor", "Hand Cursor" },
121         { "AWT.MoveCursor", "Move Cursor" },
122     };
123 
124     /**
125      * The chosen cursor type initially set to
126      * the <code>DEFAULT_CURSOR</code>.
127      *
128      * @serial
129      * @see #getType()
130      */
131     int type = DEFAULT_CURSOR;
132 
133     /**
134      * The type associated with all custom cursors.
135      */
136     public static final int CUSTOM_CURSOR           = -1;
137 
138     /*
139      * hashtable, filesystem dir prefix, filename, and properties for custom cursors support
140      */
141 
142     private static final Hashtable    systemCustomCursors         = new Hashtable  (1);
143     private static final String   systemCustomCursorDirPrefix = initCursorDir();
144 
145     private static String   initCursorDir() {
146     String   jhome =  (String  ) java.security.AccessController.doPrivileged(
147                new sun.security.action.GetPropertyAction("java.home"));
148     return jhome +
149         File.separator + "lib" + File.separator + "images" +
150         File.separator + "cursors" + File.separator;
151     }
152 
153     private static final String       systemCustomCursorPropertiesFile = systemCustomCursorDirPrefix + "cursors.properties";
154 
155     private static       Properties   systemCustomCursorProperties = null;
156 
157     private static final String   CursorDotPrefix  = "Cursor.";
158     private static final String   DotFileSuffix    = ".File";
159     private static final String   DotHotspotSuffix = ".HotSpot";
160     private static final String   DotNameSuffix    = ".Name";
161 
162     /*
163      * JDK 1.1 serialVersionUID
164      */
165     private static final long serialVersionUID = 8028237497568985504L;
166 
167     private static final DebugHelper dbg = DebugHelper.create(Cursor  .class);
168 
169     static {
170         /* ensure that the necessary native libraries are loaded */
171     Toolkit.loadLibraries();
172         if (!GraphicsEnvironment.isHeadless()) {
173             initIDs();
174         }
175     }
176 
177     /**
178      * Initialize JNI field and method IDs for fields that may be
179      * accessed from C.
180      */
181     private static native void initIDs();
182 
183     /**
184      * Hook into native data.
185      */
186     private transient long pData;
187 
188     private transient Object   anchor = new Object  ();
189 
190     static class CursorDisposer extends sun.java2d.DisposerRecord {
191         long pData;
192         public void dispose() {
193             finalizeImpl(pData);
194         }
195     }
196     transient CursorDisposer disposer;
197     private void setPData(long pData) {
198         this.pData = pData;
199         if (!GraphicsEnvironment.isHeadless() && pData != 0) {
200             if (disposer == null) {
201                 // anchor is null after deserialization
202                 if (anchor == null) {
203                     anchor = new Object  ();
204                 }
205                 disposer = new CursorDisposer();
206                 sun.java2d.Disposer.addRecord(anchor, disposer);
207             }
208             disposer.pData = pData;                
209         }
210     }
211 
212     /**
213      * The user-visible name of the cursor.
214      *
215      * @serial
216      * @see #getName()
217      */
218     protected String   name;
219 
220     /**
221      * Returns a cursor object with the specified predefined type.
222      * 
223      * @param type the type of predefined cursor
224      * @return the specified predefined cursor 
225      * @throws IllegalArgumentException if the specified cursor type is
226      *         invalid
227      */
228     static public Cursor   getPredefinedCursor(int type) {
229     if (type < Cursor.DEFAULT_CURSOR || type > Cursor.MOVE_CURSOR) {
230         throw new IllegalArgumentException  ("illegal cursor type");
231     }
232     if (predefined[type] == null) {
233         predefined[type] = new Cursor  (type);
234     }
235     return predefined[type];
236     }
237 
238     /**
239      * Returns a system-specific custom cursor object matching the 
240      * specified name.  Cursor names are, for example: "Invalid.16x16"
241      * 
242      * @param name a string describing the desired system-specific custom cursor 
243      * @return the system specific custom cursor named
244      * @exception HeadlessException if
245      * <code>GraphicsEnvironment.isHeadless</code> returns true
246      */
247     static public Cursor   getSystemCustomCursor(final String   name)
248     throws AWTException  , HeadlessException   {
249         GraphicsEnvironment.checkHeadless();
250     Cursor   cursor = (Cursor  )systemCustomCursors.get(name);
251 
252     if (cursor == null) {
253         synchronized(systemCustomCursors) {
254         if (systemCustomCursorProperties == null)
255             loadSystemCustomCursorProperties();
256         }
257 
258         String   prefix = CursorDotPrefix + name;
259         String   key    = prefix + DotFileSuffix;
260 
261         if (!systemCustomCursorProperties.containsKey(key)) {
262             if (dbg.on) {
263                 dbg.println("Cursor.getSystemCustomCursor(" + name + ") returned null");
264             } 
265             return null;
266         }
267 
268         final String   fileName =
269         systemCustomCursorProperties.getProperty(key);
270 
271         String   localized = (String  )systemCustomCursorProperties.getProperty(prefix + DotNameSuffix);
272 
273         if (localized == null) localized = name;
274 
275         String   hotspot = (String  )systemCustomCursorProperties.getProperty(prefix + DotHotspotSuffix);
276 
277         if (hotspot == null)
278             throw new AWTException  ("no hotspot property defined for cursor: " + name);
279 
280         StringTokenizer   st = new StringTokenizer  (hotspot, ",");
281 
282         if (st.countTokens() != 2)
283             throw new AWTException  ("failed to parse hotspot property for cursor: " + name);
284 
285         int x = 0;
286         int y = 0;
287 
288         try {
289         x = Integer.parseInt(st.nextToken());
290         y = Integer.parseInt(st.nextToken());
291         } catch (NumberFormatException   nfe) {
292             throw new AWTException  ("failed to parse hotspot property for cursor: " + name);
293         }
294 
295         try {
296         final int fx = x;
297         final int fy = y;
298         final String   flocalized = localized;
299 
300                 cursor = (Cursor  ) java.security.AccessController.doPrivileged(
301             new java.security.PrivilegedExceptionAction  () {
302             public Object   run() throws Exception   {
303             Toolkit   toolkit = Toolkit.getDefaultToolkit();
304             Image   image = toolkit.getImage(
305                systemCustomCursorDirPrefix + fileName);
306             return toolkit.createCustomCursor(
307                     image, new Point  (fx,fy), flocalized);
308             }
309         });
310         } catch (Exception   e) {
311         throw new AWTException  (
312                     "Exception: " + e.getClass() + " " + e.getMessage() +
313                     " occurred while creating cursor " + name);
314         }
315 
316         if (cursor == null) {
317             if (dbg.on) {
318                 dbg.println("Cursor.getSystemCustomCursor(" + name + ") returned null");
319         } 
320         } else {
321             systemCustomCursors.put(name, cursor);
322         }
323     }
324 
325     return cursor;
326     }
327 
328     /**
329      * Return the system default cursor.
330      */
331     static public Cursor   getDefaultCursor() {
332         return getPredefinedCursor(Cursor.DEFAULT_CURSOR);
333     }
334 
335     /**
336      * Creates a new cursor object with the specified type.
337      * @param type the type of cursor
338      * @throws IllegalArgumentException if the specified cursor type
339      * is invalid
340      */
341     public Cursor(int type) {
342     if (type < Cursor.DEFAULT_CURSOR || type > Cursor.MOVE_CURSOR) {
343         throw new IllegalArgumentException  ("illegal cursor type");
344     }
345     this.type = type;
346 
347         // Lookup localized name.
348         name = Toolkit.getProperty(cursorProperties[type][0],
349                                    cursorProperties[type][1]);
350     }
351 
352     /**
353      * Creates a new custom cursor object with the specified name.<p>
354      * Note:  this constructor should only be used by AWT implementations
355      * as part of their support for custom cursors.  Applications should
356      * use Toolkit.createCustomCursor().
357      * @param name the user-visible name of the cursor.
358      * @see java.awt.Toolkit#createCustomCursor
359      */
360     protected Cursor(String   name) {
361         this.type = Cursor.CUSTOM_CURSOR;
362         this.name = name;
363     }
364 
365     /**
366      * Returns the type for this cursor.
367      */
368     public int getType() {
369     return type;
370     }
371 
372     /**
373      * Returns the name of this cursor.
374      * @return    a localized description of this cursor.
375      * @since     1.2
376      */
377     public String   getName() {
378     return name;
379     }
380 
381     /**
382      * Returns a string representation of this cursor.
383      * @return    a string representation of this cursor.
384      * @since     1.2
385      */
386     public String   toString() {
387     return getClass().getName() + "[" + getName() + "]";
388     }
389 
390     /*
391      * load the cursor.properties file
392      */
393     private static void loadSystemCustomCursorProperties() throws AWTException   {
394     synchronized(systemCustomCursors) {
395         systemCustomCursorProperties = new Properties  ();
396 
397             try {
398             AccessController.doPrivileged(
399                       new java.security.PrivilegedExceptionAction  () {
400             public Object   run() throws Exception   {
401             FileInputStream   fis = null;
402             try {
403                 fis = new FileInputStream  (
404                        systemCustomCursorPropertiesFile);
405                 systemCustomCursorProperties.load(fis);
406             } finally {
407                 if (fis != null)
408                 fis.close();
409             }
410             return null;
411             }
412         });
413         } catch (Exception   e) {
414         systemCustomCursorProperties = null;
415          throw new AWTException  ("Exception: " + e.getClass() + " " +
416            e.getMessage() + " occurred while loading: " +
417                     systemCustomCursorPropertiesFile);
418         }
419         }
420     }
421 
422     private native static void finalizeImpl(long pData);
423 }
424 
425
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