1 /*
   2  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 package java.awt;
  26 
  27 import java.io.IOException;
  28 import java.awt.image.*;
  29 import java.net.URL;
  30 import java.net.URLConnection;
  31 import java.io.File;
  32 import sun.util.logging.PlatformLogger;
  33 import sun.awt.image.SunWritableRaster;
  34 
  35 /**
  36  * The splash screen can be displayed at application startup, before the
  37  * Java Virtual Machine (JVM) starts. The splash screen is displayed as an
  38  * undecorated window containing an image. You can use GIF, JPEG, or PNG files
  39  * for the image. Animation is supported for the GIF format, while transparency
  40  * is supported both for GIF and PNG.  The window is positioned at the center
  41  * of the screen. The position on multi-monitor systems is not specified. It is
  42  * platform and implementation dependent.  The splash screen window is closed
  43  * automatically as soon as the first window is displayed by Swing/AWT (may be
  44  * also closed manually using the Java API, see below).
  45  * <P>
  46  * If your application is packaged in a jar file, you can use the
  47  * "SplashScreen-Image" option in a manifest file to show a splash screen.
  48  * Place the image in the jar archive and specify the path in the option.
  49  * The path should not have a leading slash.
  50  * <BR>
  51  * For example, in the <code>manifest.mf</code> file:
  52  * <PRE>
  53  * Manifest-Version: 1.0
  54  * Main-Class: Test
  55  * SplashScreen-Image: filename.gif
  56  * </PRE>
  57  * <P>
  58  * If the Java implementation provides the command-line interface and you run
  59  * your application by using the command line or a shortcut, use the Java
  60  * application launcher option to show a splash screen. The Oracle reference
  61  * implementation allows you to specify the splash screen image location with
  62  * the {@code -splash:} option.
  63  * <BR>
  64  * For example:
  65  * <PRE>
  66  * java -splash:filename.gif Test
  67  * </PRE>
  68  * The command line interface has higher precedence over the manifest
  69  * setting.
  70  * <p>
  71  * The splash screen will be displayed as faithfully as possible to present the
  72  * whole splash screen image given the limitations of the target platform and
  73  * display.
  74  * <p>
  75  * It is implied that the specified image is presented on the screen "as is",
  76  * i.e. preserving the exact color values as specified in the image file. Under
  77  * certain circumstances, though, the presented image may differ, e.g. when
  78  * applying color dithering to present a 32 bits per pixel (bpp) image on a 16
  79  * or 8 bpp screen. The native platform display configuration may also affect
  80  * the colors of the displayed image (e.g.  color profiles, etc.)
  81  * <p>
  82  * The {@code SplashScreen} class provides the API for controlling the splash
  83  * screen. This class may be used to close the splash screen, change the splash
  84  * screen image, get the splash screen native window position/size, and paint
  85  * in the splash screen. It cannot be used to create the splash screen. You
  86  * should use the options provided by the Java implementation for that.
  87  * <p>
  88  * This class cannot be instantiated. Only a single instance of this class
  89  * can exist, and it may be obtained by using the {@link #getSplashScreen()}
  90  * static method. In case the splash screen has not been created at
  91  * application startup via the command line or manifest file option,
  92  * the <code>getSplashScreen</code> method returns <code>null</code>.
  93  *
  94  * @author Oleg Semenov
  95  * @since 1.6
  96  */
  97 public final class SplashScreen {
  98 
  99     SplashScreen(long ptr) { // non-public constructor
 100         splashPtr = ptr;
 101     }
 102 
 103     /**
 104      * Returns the {@code SplashScreen} object used for
 105      * Java startup splash screen control on systems that support display.
 106      *
 107      * @throws UnsupportedOperationException if the splash screen feature is not
 108      *         supported by the current toolkit
 109      * @throws HeadlessException if {@code GraphicsEnvironment.isHeadless()}
 110      *         returns true
 111      * @return the {@link SplashScreen} instance, or <code>null</code> if there is
 112      *         none or it has already been closed
 113      */
 114     public static  SplashScreen getSplashScreen() {
 115         synchronized (SplashScreen.class) {
 116             if (GraphicsEnvironment.isHeadless()) {
 117                 throw new HeadlessException();
 118             }
 119             // SplashScreen class is now a singleton
 120             if (!wasClosed && theInstance == null) {
 121                 java.security.AccessController.doPrivileged(
 122                         new sun.security.action.LoadLibraryAction("splashscreen"));
 123                 long ptr = _getInstance();
 124                 if (ptr != 0 && _isVisible(ptr)) {
 125                     theInstance = new SplashScreen(ptr);
 126                 }
 127             }
 128             return theInstance;
 129         }
 130     }
 131 
 132     /**
 133      * Changes the splash screen image. The new image is loaded from the
 134      * specified URL; GIF, JPEG and PNG image formats are supported.
 135      * The method returns after the image has finished loading and the window
 136      * has been updated.
 137      * The splash screen window is resized according to the size of
 138      * the image and is centered on the screen.
 139      *
 140      * @param imageURL the non-<code>null</code> URL for the new
 141      *        splash screen image
 142      * @throws NullPointerException if {@code imageURL} is <code>null</code>
 143      * @throws IOException if there was an error while loading the image
 144      * @throws IllegalStateException if the splash screen has already been
 145      *         closed
 146      */
 147     public void setImageURL(URL imageURL) throws NullPointerException, IOException, IllegalStateException {
 148         checkVisible();
 149         URLConnection connection = imageURL.openConnection();
 150         connection.connect();
 151         int length = connection.getContentLength();
 152         java.io.InputStream stream = connection.getInputStream();
 153         byte[] buf = new byte[length];
 154         int off = 0;
 155         while(true) {
 156             // check for available data
 157             int available = stream.available();
 158             if (available <= 0) {
 159                 // no data available... well, let's try reading one byte
 160                 // we'll see what happens then
 161                 available = 1;
 162             }
 163             // check for enough room in buffer, realloc if needed
 164             // the buffer always grows in size 2x minimum
 165             if (off + available > length) {
 166                 length = off*2;
 167                 if (off + available > length) {
 168                     length = available+off;
 169                 }
 170                 byte[] oldBuf = buf;
 171                 buf = new byte[length];
 172                 System.arraycopy(oldBuf, 0, buf, 0, off);
 173             }
 174             // now read the data
 175             int result = stream.read(buf, off, available);
 176             if (result < 0) {
 177                 break;
 178             }
 179             off += result;
 180         }
 181         synchronized(SplashScreen.class) {
 182             checkVisible();
 183             if (!_setImageData(splashPtr, buf)) {
 184                 throw new IOException("Bad image format or i/o error when loading image");
 185             }
 186             this.imageURL = imageURL;
 187         }
 188     }
 189 
 190     private void checkVisible() {
 191         if (!isVisible()) {
 192             throw new IllegalStateException("no splash screen available");
 193         }
 194     }
 195     /**
 196      * Returns the current splash screen image.
 197      *
 198      * @return URL for the current splash screen image file
 199      * @throws IllegalStateException if the splash screen has already been closed
 200      */
 201     public URL getImageURL() throws IllegalStateException {
 202         synchronized (SplashScreen.class) {
 203             checkVisible();
 204             if (imageURL == null) {
 205                 try {
 206                     String fileName = _getImageFileName(splashPtr);
 207                     String jarName = _getImageJarName(splashPtr);
 208                     if (fileName != null) {
 209                         if (jarName != null) {
 210                             imageURL = new URL("jar:"+(new File(jarName).toURL().toString())+"!/"+fileName);
 211                         } else {
 212                             imageURL = new File(fileName).toURL();
 213                         }
 214                     }
 215                 }
 216                 catch(java.net.MalformedURLException e) {
 217                     if (log.isLoggable(PlatformLogger.FINE)) {
 218                         log.fine("MalformedURLException caught in the getImageURL() method", e);
 219                     }
 220                 }
 221             }
 222             return imageURL;
 223         }
 224     }
 225 
 226     /**
 227      * Returns the bounds of the splash screen window as a {@link Rectangle}.
 228      * This may be useful if, for example, you want to replace the splash
 229      * screen with your window at the same location.
 230      * <p>
 231      * You cannot control the size or position of the splash screen.
 232      * The splash screen size is adjusted automatically when the image changes.
 233      * <p>
 234      * The image may contain transparent areas, and thus the reported bounds may
 235      * be larger than the visible splash screen image on the screen.
 236      *
 237      * @return a {@code Rectangle} containing the splash screen bounds
 238      * @throws IllegalStateException if the splash screen has already been closed
 239      */
 240     public Rectangle getBounds() throws IllegalStateException {
 241         synchronized (SplashScreen.class) {
 242             checkVisible();
 243             return _getBounds(splashPtr);
 244         }
 245     }
 246 
 247     /**
 248      * Returns the size of the splash screen window as a {@link Dimension}.
 249      * This may be useful if, for example,
 250      * you want to draw on the splash screen overlay surface.
 251      * <p>
 252      * You cannot control the size or position of the splash screen.
 253      * The splash screen size is adjusted automatically when the image changes.
 254      * <p>
 255      * The image may contain transparent areas, and thus the reported size may
 256      * be larger than the visible splash screen image on the screen.
 257      *
 258      * @return a {@link Dimension} object indicating the splash screen size
 259      * @throws IllegalStateException if the splash screen has already been closed
 260      */
 261     public Dimension getSize() throws IllegalStateException {
 262         return getBounds().getSize();
 263     }
 264 
 265     /**
 266      * Creates a graphics context (as a {@link Graphics2D} object) for the splash
 267      * screen overlay image, which allows you to draw over the splash screen.
 268      * Note that you do not draw on the main image but on the image that is
 269      * displayed over the main image using alpha blending. Also note that drawing
 270      * on the overlay image does not necessarily update the contents of splash
 271      * screen window. You should call {@code update()} on the
 272      * <code>SplashScreen</code> when you want the splash screen to be
 273      * updated immediately.
 274      * <p>
 275      * The pixel (0, 0) in the coordinate space of the graphics context
 276      * corresponds to the origin of the splash screen native window bounds (see
 277      * {@link #getBounds()}).
 278      *
 279      * @return graphics context for the splash screen overlay surface
 280      * @throws IllegalStateException if the splash screen has already been closed
 281      */
 282     public Graphics2D createGraphics() throws IllegalStateException {
 283         synchronized (SplashScreen.class) {
 284             if (image==null) {
 285                 Dimension dim = getSize();
 286                 image = new BufferedImage(dim.width, dim.height, BufferedImage.TYPE_INT_ARGB);
 287             }
 288             return image.createGraphics();
 289         }
 290     }
 291 
 292     /**
 293      * Updates the splash window with current contents of the overlay image.
 294      *
 295      * @throws IllegalStateException if the overlay image does not exist;
 296      *         for example, if {@code createGraphics} has never been called,
 297      *         or if the splash screen has already been closed
 298      */
 299     public void update() throws IllegalStateException {
 300         BufferedImage image;
 301         synchronized (SplashScreen.class) {
 302             checkVisible();
 303             image = this.image;
 304         }
 305         if (image == null) {
 306             throw new IllegalStateException("no overlay image available");
 307         }
 308         DataBuffer buf = image.getRaster().getDataBuffer();
 309         if (!(buf instanceof DataBufferInt)) {
 310             throw new AssertionError("Overlay image DataBuffer is of invalid type == "+buf.getClass().getName());
 311         }
 312         int numBanks = buf.getNumBanks();
 313         if (numBanks!=1) {
 314             throw new AssertionError("Invalid number of banks =="+numBanks+" in overlay image DataBuffer");
 315         }
 316         if (!(image.getSampleModel() instanceof SinglePixelPackedSampleModel)) {
 317             throw new AssertionError("Overlay image has invalid sample model == "+image.getSampleModel().getClass().getName());
 318         }
 319         SinglePixelPackedSampleModel sm = (SinglePixelPackedSampleModel)image.getSampleModel();
 320         int scanlineStride = sm.getScanlineStride();
 321         Rectangle rect = image.getRaster().getBounds();
 322         // Note that we steal the data array here, but just for reading
 323         // so we do not need to mark the DataBuffer dirty...
 324         int[] data = SunWritableRaster.stealData((DataBufferInt)buf, 0);
 325         synchronized(SplashScreen.class) {
 326             checkVisible();
 327             _update(splashPtr, data, rect.x, rect.y, rect.width, rect.height, scanlineStride);
 328         }
 329     }
 330 
 331     /**
 332      * Hides the splash screen, closes the window, and releases all associated
 333      * resources.
 334      *
 335      * @throws IllegalStateException if the splash screen has already been closed
 336      */
 337     public void close() throws IllegalStateException {
 338         synchronized (SplashScreen.class) {
 339             checkVisible();
 340             _close(splashPtr);
 341             image = null;
 342             SplashScreen.markClosed();
 343         }
 344     }
 345 
 346     static void markClosed() {
 347         synchronized (SplashScreen.class) {
 348             wasClosed = true;
 349             theInstance = null;
 350         }
 351     }
 352 
 353 
 354     /**
 355      * Determines whether the splash screen is visible. The splash screen may
 356      * be hidden using {@link #close()}, it is also hidden automatically when
 357      * the first AWT/Swing window is made visible.
 358      * <p>
 359      * Note that the native platform may delay presenting the splash screen
 360      * native window on the screen. The return value of {@code true} for this
 361      * method only guarantees that the conditions to hide the splash screen
 362      * window have not occurred yet.
 363      *
 364      * @return true if the splash screen is visible (has not been closed yet),
 365      *         false otherwise
 366      */
 367     public boolean isVisible() {
 368         synchronized (SplashScreen.class) {
 369             return !wasClosed && _isVisible(splashPtr);
 370         }
 371     }
 372 
 373     private BufferedImage image; // overlay image
 374 
 375     private final long splashPtr; // pointer to native Splash structure
 376     private static boolean wasClosed = false;
 377 
 378     private URL imageURL;
 379 
 380     /**
 381      * The instance reference for the singleton.
 382      * (<code>null</code> if no instance exists yet.)
 383      *
 384      * @see #getSplashScreen
 385      * @see #close
 386      */
 387     private static SplashScreen theInstance = null;
 388 
 389     private static final PlatformLogger log = PlatformLogger.getLogger("java.awt.SplashScreen");
 390 
 391     private native static void _update(long splashPtr, int[] data, int x, int y, int width, int height, int scanlineStride);
 392     private native static boolean _isVisible(long splashPtr);
 393     private native static Rectangle _getBounds(long splashPtr);
 394     private native static long _getInstance();
 395     private native static void _close(long splashPtr);
 396     private native static String _getImageFileName(long splashPtr);
 397     private native static String _getImageJarName(long SplashPtr);
 398     private native static boolean _setImageData(long SplashPtr, byte[] data);
 399 
 400 };