libjava/java/awt/MediaTracker.java

   1 /* MediaTracker.java -- Class used for keeping track of images
   2    Copyright (C) 1999, 2002 Free Software Foundation, Inc.
   3
   4 This file is part of GNU Classpath.
   5
   6 GNU Classpath is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU Classpath is distributed in the hope that it will be useful, but
  12 WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Classpath; see the file COPYING.  If not, write to the
  18 Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  19 02111-1307 USA.
  20
  21 Linking this library statically or dynamically with other modules is
  22 making a combined work based on this library.  Thus, the terms and
  23 conditions of the GNU General Public License cover the whole
  24 combination.
  25
  26 As a special exception, the copyright holders of this library give you
  27 permission to link this library with independent modules to produce an
  28 executable, regardless of the license terms of these independent
  29 modules, and to copy and distribute the resulting executable under
  30 terms of your choice, provided that you also meet, for each linked
  31 independent module, the terms and conditions of the license of that
  32 module.  An independent module is a module which is not derived from
  33 or based on this library.  If you modify this library, you may extend
  34 this exception to your version of the library, but you are not
  35 obligated to do so.  If you do not wish to do so, delete this
  36 exception statement from your version. */
  37
  38
  39 package java.awt;
  40
  41 import java.util.ArrayList;
  42 import java.awt.image.ImageObserver;
  43
  44 /**
  45   * This class is used for keeping track of the status of various media
  46   * objects.
  47   *
  48   * @author Aaron M. Renn (arenn@urbanophile.com)
  49   * @author Bryce McKinlay
  50   */
  51 public class MediaTracker implements java.io.Serializable
  52 {
  53   public static final int LOADING = 1 << 0;
  54   public static final int ABORTED = 1 << 1;
  55   public static final int ERRORED = 1 << 2;
  56   public static final int COMPLETE = 1 << 3;
  57
  58   Component target;
  59   MediaEntry head;
  60
  61   static final long serialVersionUID = -483174189758638095L;
  62
  63   // FIXME: The serialized form documentation says MediaEntry is a
  64   // serializable field, but the serialized form of MediaEntry itself
  65   // doesn't appear to be documented.
  66   class MediaEntry implements ImageObserver
  67   {
  68     int id;
  69     Image image;
  70     MediaEntry next;
  71     int status;
  72     int width;
  73     int height;
  74
  75     public boolean imageUpdate(Image img, int flags, int x, int y,
  76                                int width, int height)
  77     {
  78       if ((flags & ABORT) != 0)
  79         status = ABORTED | COMPLETE;
  80       else if ((flags & ERROR) != 0)
  81         status = ERRORED | COMPLETE;
  82       else if ((flags & ALLBITS) != 0)
  83         status = COMPLETE;
  84       else
  85         status = LOADING;
  86
  87       synchronized (MediaTracker.this)
  88       {
  89         MediaTracker.this.notifyAll();
  90       }
  91       // If status is not COMPLETE then we need more updates.
  92       return (status & COMPLETE) == 0;
  93     }
  94   }
  95
  96   public MediaTracker(Component c)
  97   {
  98     target = c;
  99   }
 100
 101   public void addImage(Image image, int id)
 102   {
 103     MediaEntry e = new MediaEntry();
 104     e.id = id;
 105     e.image = image;
 106     e.next = head;
 107     head = e;
 108     // Start tracking image status.
 109     target.checkImage(image, e);
 110   }
 111
 112   public void addImage(Image image, int id, int width, int height)
 113   {
 114     MediaEntry e = new MediaEntry();
 115     e.id = id;
 116     e.image = image;
 117     e.next = head;
 118     e.width = width;
 119     e.height = height;
 120     head = e;
 121     // Start tracking image status.
 122     target.checkImage(image, width, height, e);
 123   }
 124
 125   public boolean checkAll()
 126   {
 127     return checkAll(false);
 128   }
 129
 130   public boolean checkAll(boolean load)
 131   {
 132     MediaEntry e = head;
 133     boolean result = true;
 134
 135     while (e != null)
 136       {
 137         if ((e.status & COMPLETE) == 0)
 138           {
 139             if (load)
 140               {
 141                 result = false;
 142                 if (e.status == 0)
 143                   {
 144                     target.prepareImage(e.image, e);
 145                     e.status = LOADING;
 146                   }
 147               }
 148             else
 149               return false;
 150           }
 151         e = e.next;
 152       }
 153     return result;
 154   }
 155
 156   public boolean isErrorAny()
 157   {
 158     MediaEntry e = head;
 159     while (e != null)
 160       {
 161         if ((e.status & ERRORED) != 0)
 162           return true;
 163         e = e.next;
 164       }
 165     return false;
 166   }
 167
 168   public Object[] getErrorsAny()
 169   {
 170     MediaEntry e = head;
 171     ArrayList result = null;
 172     while (e != null)
 173       {
 174         if ((e.status & ERRORED) != 0)
 175           {
 176             if (result == null)
 177               result = new ArrayList();
 178             result.add(e.image);
 179           }
 180         e = e.next;
 181       }
 182     if (result == null)
 183       return null;
 184     else
 185       return result.toArray();
 186   }
 187
 188   public void waitForAll() throws InterruptedException
 189   {
 190     synchronized (this)
 191     {
 192       while (checkAll(true) == false)
 193         wait();
 194     }
 195   }
 196
 197   public boolean waitForAll(long ms) throws InterruptedException
 198   {
 199     long start = System.currentTimeMillis();
 200     synchronized (this)
 201     {
 202       while (!checkAll(true))
 203         wait(ms);
 204     }
 205     if ((System.currentTimeMillis() - start) < ms)
 206       return true;
 207     else
 208       return false;
 209   }
 210
 211   public int statusAll(boolean load)
 212   {
 213     int result = 0;
 214     MediaEntry e = head;
 215     while (e != null)
 216       {
 217         if (load && e.status == 0)
 218           {
 219             target.prepareImage(e.image, e);
 220             e.status = LOADING;
 221           }
 222         result |= e.status;
 223         e = e.next;
 224       }
 225     return result;
 226   }
 227
 228   public boolean checkID(int id)
 229   {
 230     return checkID(id, false);
 231   }
 232
 233   public boolean checkID(int id, boolean load)
 234   {
 235     MediaEntry e = head;
 236     boolean result = true;
 237
 238     while (e != null)
 239       {
 240         if (e.id == id && ((e.status & COMPLETE) == 0))
 241           {
 242             if (load)
 243               {
 244                 result = false;
 245                 if (e.status == 0)
 246                   {
 247                     target.prepareImage(e.image, e);
 248                     e.status = LOADING;
 249                   }
 250               }
 251             else
 252               return false;
 253           }
 254         e = e.next;
 255       }
 256     return result;
 257   }
 258
 259   public boolean isErrorID(int id)
 260   {
 261     MediaEntry e = head;
 262     while (e != null)
 263       {
 264         if (e.id == id && ((e.status & ERRORED) != 0))
 265           return true;
 266         e = e.next;
 267       }
 268     return false;
 269   }
 270
 271   public Object[] getErrorsID(int id)
 272   {
 273     MediaEntry e = head;
 274     ArrayList result = null;
 275     while (e != null)
 276       {
 277         if (e.id == id && ((e.status & ERRORED) != 0))
 278           {
 279             if (result == null)
 280               result = new ArrayList();
 281             result.add(e.image);
 282           }
 283         e = e.next;
 284       }
 285     if (result == null)
 286       return null;
 287     else
 288       return result.toArray();
 289   }
 290
 291   public void waitForID(int id) throws InterruptedException
 292   {
 293     MediaEntry e = head;
 294     synchronized (this)
 295     {
 296       while (checkID (id, true) == false)
 297         wait();
 298     }
 299   }
 300
 301   public boolean waitForID(int id, long ms) throws InterruptedException
 302   {
 303     MediaEntry e = head;
 304     long start = System.currentTimeMillis();
 305     synchronized (this)
 306     {
 307       while (checkID (id, true) == false)
 308         wait(ms);
 309     }
 310     if ((System.currentTimeMillis() - start) < ms)
 311       return true;
 312     else
 313       return false;
 314   }
 315
 316   public int statusID(int id, boolean load)
 317   {
 318     int result = 0;
 319     MediaEntry e = head;
 320     while (e != null)
 321       {
 322         if (e.id == id)
 323           {
 324             if (load && e.status == 0)
 325               {
 326                 target.prepareImage(e.image, e);
 327                 e.status = LOADING;
 328               }
 329             result |= e.status;
 330           }
 331         e = e.next;
 332       }
 333     return result;
 334   }
 335
 336   public void removeImage(Image image)
 337   {
 338     MediaEntry e = head;
 339     MediaEntry prev = null;
 340     while (e != null)
 341       {
 342         if (e.image == image)
 343           {
 344             if (prev == null)
 345               head = e.next;
 346             else
 347               prev.next = e.next;
 348           }
 349         prev = e;
 350         e = e.next;
 351       }
 352   }
 353
 354   public void removeImage(Image image, int id)
 355   {
 356     MediaEntry e = head;
 357     MediaEntry prev = null;
 358     while (e != null)
 359       {
 360         if (e.id == id && e.image == image)
 361           {
 362             if (prev == null)
 363               head = e.next;
 364             else
 365               prev.next = e.next;
 366           }
 367         else
 368           prev = e;
 369         e = e.next;
 370       }
 371   }
 372
 373   public void removeImage(Image image, int id, int width, int height)
 374   {
 375     MediaEntry e = head;
 376     MediaEntry prev = null;
 377     while (e != null)
 378       {
 379         if (e.id == id && e.image == image
 380             && e.width == width && e.height == height)
 381           {
 382             if (prev == null)
 383               head = e.next;
 384             else
 385               prev.next = e.next;
 386           }
 387         else
 388           prev = e;
 389         e = e.next;
 390       }
 391   }
 392 }