001/* ProgressMonitor.java -- 002 Copyright (C) 2002, 2004, 2005, 2006, Free Software Foundation, Inc. 003 004This file is part of GNU Classpath. 005 006GNU Classpath is free software; you can redistribute it and/or modify 007it under the terms of the GNU General Public License as published by 008the Free Software Foundation; either version 2, or (at your option) 009any later version. 010 011GNU Classpath is distributed in the hope that it will be useful, but 012WITHOUT ANY WARRANTY; without even the implied warranty of 013MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 014General Public License for more details. 015 016You should have received a copy of the GNU General Public License 017along with GNU Classpath; see the file COPYING. If not, write to the 018Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 01902110-1301 USA. 020 021Linking this library statically or dynamically with other modules is 022making a combined work based on this library. Thus, the terms and 023conditions of the GNU General Public License cover the whole 024combination. 025 026As a special exception, the copyright holders of this library give you 027permission to link this library with independent modules to produce an 028executable, regardless of the license terms of these independent 029modules, and to copy and distribute the resulting executable under 030terms of your choice, provided that you also meet, for each linked 031independent module, the terms and conditions of the license of that 032module. An independent module is a module which is not derived from 033or based on this library. If you modify this library, you may extend 034this exception to your version of the library, but you are not 035obligated to do so. If you do not wish to do so, delete this 036exception statement from your version. */ 037 038package javax.swing; 039 040import java.awt.Component; 041import java.awt.event.ActionEvent; 042import java.awt.event.ActionListener; 043 044import javax.accessibility.AccessibleContext; 045 046/** 047 * <p>Using this class you can easily monitor tasks where you cannot 048 * estimate the duration exactly.</p> 049 * 050 * <p>A ProgressMonitor instance waits until the first time setProgress 051 * is called. When <code>millisToDecideToPopup</code> time elapsed the 052 * instance estimates the duration until the whole operation is completed. 053 * If this duration exceeds <code>millisToPopup</code> a non-modal dialog 054 * with a message and a progress bar is shown.</p> 055 * 056 * <p>The value of <code>millisToDecideToPopup</code> defaults to 057 * <code>500</code> and <code>millisToPopup</code> to 058 * <code>2000</code>.</p> 059 * 060 * @author Andrew Selkirk 061 * @author Robert Schuster (robertschuster@fsfe.org) 062 * @since 1.2 063 * @status updated to 1.2 064 */ 065public class ProgressMonitor 066{ 067 068 /** 069 * The accessible content for this component 070 */ 071 protected AccessibleContext accessibleContext; 072 073 /** 074 * parentComponent 075 */ 076 Component component; 077 078 /** 079 * note 080 */ 081 String note; 082 083 /** 084 * message 085 */ 086 Object message; 087 088 /** 089 * millisToDecideToPopup 090 */ 091 int millisToDecideToPopup = 500; 092 093 /** 094 * millisToPopup 095 */ 096 int millisToPopup = 2000; 097 098 int min, max, progress; 099 100 JProgressBar progressBar; 101 102 JLabel noteLabel; 103 104 JDialog progressDialog; 105 106 Timer timer; 107 108 boolean canceled; 109 110 /** 111 * Creates a new <code>ProgressMonitor</code> instance. This is used to 112 * monitor a task and pops up a dialog if the task is taking a long time to 113 * run. 114 * 115 * @param component The parent component of the progress dialog or 116 * <code>null</code>. 117 * @param message A constant message object which works in the way it does 118 * in {@link JOptionPane}. 119 * @param note A string message which can be changed while the operation goes 120 * on. 121 * @param minimum The minimum value for the operation (start value). 122 * @param maximum The maximum value for the operation (end value). 123 */ 124 public ProgressMonitor(Component component, Object message, 125 String note, int minimum, int maximum) 126 { 127 128 // Set data. 129 this.component = component; 130 this.message = message; 131 this.note = note; 132 133 min = minimum; 134 max = maximum; 135 } 136 137 /** 138 * <p>Hides the dialog and stops any measurements.</p> 139 * 140 * <p>Has no effect when <code>setProgress</code> is not at least 141 * called once.</p> 142 */ 143 public void close() 144 { 145 if (progressDialog != null) 146 { 147 progressDialog.setVisible(false); 148 } 149 150 if (timer != null) 151 { 152 timer.stop(); 153 timer = null; 154 } 155 } 156 157 /** 158 * <p>Updates the progress value.</p> 159 * 160 * <p>When called for the first time this initializes a timer 161 * which decides after <code>millisToDecideToPopup</code> time 162 * whether to show a progress dialog or not.</p> 163 * 164 * <p>If the progress value equals or exceeds the maximum 165 * value the progress dialog is closed automatically.</p> 166 * 167 * @param progress New progress value. 168 */ 169 public void setProgress(int progress) 170 { 171 this.progress = progress; 172 173 // Initializes and starts a timer with a task 174 // which measures the duration and displays 175 // a progress dialog if neccessary. 176 if (timer == null && progressDialog == null) 177 { 178 timer = new Timer(25, null); 179 timer.addActionListener(new TimerListener()); 180 timer.start(); 181 } 182 183 // Cancels timer and hides progress dialog if the 184 // maximum value is reached. 185 if (progressBar != null && this.progress >= progressBar.getMaximum()) 186 { 187 // The reason for using progressBar.getMaximum() instead of max is that 188 // we want to prevent that changes to the value have any effect after the 189 // progress dialog is visible (This is how the JDK behaves.). 190 close(); 191 } 192 193 } 194 195 /** 196 * Returns the minimum or start value of the operation. 197 * 198 * @return Minimum or start value of the operation. 199 */ 200 public int getMinimum() 201 { 202 return min; 203 } 204 205 /** 206 * <p>Use this method to set the minimum or start value of 207 * your operation.</p> 208 * 209 * <p>For typical application like copy operation this will be 210 * zero.</p> 211 * 212 * <p>Keep in mind that changing this value after the progress 213 * dialog is made visible has no effect upon the progress bar.</p> 214 * 215 * @param minimum The new minimum value. 216 */ 217 public void setMinimum(int minimum) 218 { 219 min = minimum; 220 } 221 222 /** 223 * Return the maximum or end value of your operation. 224 * 225 * @return Maximum or end value. 226 */ 227 public int getMaximum() 228 { 229 return max; 230 } 231 232 /** 233 * <p>Sets the maximum or end value of the operation to the 234 * given integer.</p> 235 * 236 * @param maximum 237 */ 238 public void setMaximum(int maximum) 239 { 240 max = maximum; 241 } 242 243 /** 244 * Returns whether the user canceled the operation. 245 * 246 * @return Whether the operation was canceled. 247 */ 248 public boolean isCanceled() 249 { 250 // The value is predefined to false 251 // and changes only when the user clicks 252 // the cancel button in the progress dialog. 253 return canceled; 254 } 255 256 /** 257 * Returns the amount of milliseconds to wait 258 * until the ProgressMonitor should decide whether 259 * a progress dialog is to be shown or not. 260 * 261 * @return The duration in milliseconds. 262 */ 263 public int getMillisToDecideToPopup() 264 { 265 return millisToDecideToPopup; 266 } 267 268 /** 269 * Sets the amount of milliseconds to wait until the 270 * ProgressMonitor should decide whether a progress dialog 271 * is to be shown or not. 272 * 273 * <p>This method has no effect when the progress dialog 274 * is already visible.</p> 275 * 276 * @param time The duration in milliseconds. 277 */ 278 public void setMillisToDecideToPopup(int time) 279 { 280 millisToDecideToPopup = time; 281 } 282 283 /** 284 * Returns the number of milliseconds to wait before displaying the progress 285 * dialog. The default value is 2000. 286 * 287 * @return The number of milliseconds. 288 * 289 * @see #setMillisToPopup(int) 290 */ 291 public int getMillisToPopup() 292 { 293 return millisToPopup; 294 } 295 296 /** 297 * Sets the number of milliseconds to wait before displaying the progress 298 * dialog. 299 * 300 * @param time the number of milliseconds. 301 * 302 * @see #getMillisToPopup() 303 */ 304 public void setMillisToPopup(int time) 305 { 306 millisToPopup = time; 307 } 308 309 /** 310 * Returns a message which is shown in the progress dialog. 311 * 312 * @return The changeable message visible in the progress dialog. 313 */ 314 public String getNote() 315 { 316 return note; 317 } 318 319 /** 320 * <p>Set the message shown in the progess dialog.</p> 321 * 322 * <p>Changing the note while the progress dialog is visible 323 * is possible.</p> 324 * 325 * @param note A message shown in the progress dialog. 326 */ 327 public void setNote(String note) 328 { 329 if (noteLabel != null) 330 { 331 noteLabel.setText(note); 332 } 333 else 334 { 335 this.note = note; 336 } 337 } 338 339 /** 340 * Internal method that creates the progress dialog. 341 */ 342 void createDialog() 343 { 344 // If there is no note we suppress the generation of the 345 // label. 346 Object[] tmp = (note == null) ? 347 new Object[] 348 { 349 message, 350 progressBar = new JProgressBar(min, max) 351 } 352 : 353 new Object[] 354 { 355 message, 356 noteLabel = new JLabel(note), 357 progressBar = new JProgressBar(min, max) 358 }; 359 360 JOptionPane pane = new JOptionPane(tmp, JOptionPane.INFORMATION_MESSAGE); 361 362 // FIXME: Internationalize the button 363 JButton cancelButton = new JButton("Cancel"); 364 cancelButton.addActionListener(new ActionListener() 365 { 366 public void actionPerformed(ActionEvent ae) 367 { 368 canceled = true; 369 } 370 }); 371 372 pane.setOptions(new Object[] { cancelButton }); 373 374 // FIXME: Internationalize the title 375 progressDialog = pane.createDialog(component, "Progress ..."); 376 progressDialog.setModal(false); 377 progressDialog.setResizable(true); 378 379 progressDialog.pack(); 380 progressDialog.setVisible(true); 381 382 } 383 384 /** An ActionListener implementation which does the measurements 385 * and estimations of the ProgressMonitor. 386 */ 387 class TimerListener implements ActionListener 388 { 389 long timestamp; 390 391 int lastProgress; 392 393 boolean first = true; 394 395 TimerListener() 396 { 397 timestamp = System.currentTimeMillis(); 398 } 399 400 public void actionPerformed(ActionEvent ae) 401 { 402 long now = System.currentTimeMillis(); 403 404 if (first) 405 { 406 if ((now - timestamp) > millisToDecideToPopup) 407 { 408 first = false; 409 410 411 long expected = (progress - min == 0) ? 412 (now - timestamp) * (max - min) : 413 (now - timestamp) * (max - min) / (progress - min); 414 415 if (expected > millisToPopup) 416 { 417 createDialog(); 418 } 419 } 420 else 421 { 422 // We have not waited long enough to make a decision, 423 // so return and try again when the timer is invoked. 424 return; 425 } 426 } 427 else if (progressDialog != null) 428 { 429 // The progress dialog is being displayed. We now calculate 430 // whether setting the progress bar to the current progress 431 // value would result in a visual difference. 432 int delta = progress - progressBar.getValue(); 433 434 if ((delta * progressBar.getWidth() / (max - min)) > 0) 435 { 436 // At least one pixel would change. 437 progressBar.setValue(progress); 438 } 439 } 440 else 441 { 442 // No dialog necessary 443 timer.stop(); 444 timer = null; 445 } 446 447 timestamp = now; 448 } 449 } 450 451 /** 452 * Gets the accessible context. 453 * 454 * @return the accessible context. 455 */ 456 public AccessibleContext getAccessibleContext() 457 { 458 return accessibleContext; 459 } 460}