/**
* @(#)SplashScreen.java 1.13 06/11/21
*
* Copyright 2006 Sun Microsystems, Inc. All rights reserved.
* SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*/
package java.awt;
import java.io.IOException;
import java.awt.image.*;
import java.net.URL;
import java.net.URLConnection;
import java.io.File;
/**
* The splash screen can be created at application startup, before the
* Java Virtual Machine (JVM) starts. The splash screen is displayed as an
* undecorated window containing an image. You can use GIF, JPEG, and PNG files
* for the image. Animation (for GIF) and transparency (for GIF, PNG) are
* supported. The window is positioned at the center of the screen (the
* position on multi-monitor systems is not specified - it is platform and
* implementation dependent).
* The window is closed automatically as soon as the first window is displayed by
* Swing/AWT (may be also closed manually using the Java API, see below).
* <P>
* There are two ways to show the native splash screen:
* <P>
* <UL>
* <LI>If your application is run from the command line or from a shortcut,
* use the "-splash:" Java application launcher option to show a splash screen.
* <BR>
* For example:
* <PRE>
* java -splash:filename.gif Test
* </PRE>
* <LI>If your application is packaged in a jar file, you can use the
* "SplashScreen-Image" option in a manifest file to show a splash screen.
* Place the image in the jar archive and specify the path in the option.
* The path should not have a leading slash.
* <BR>
* For example, in the <code>manifest.mf</code> file:
* <PRE>
* Manifest-Version: 1.0
* Main-Class: Test
* SplashScreen-Image: filename.gif
* </PRE>
* The command line interface has higher precedence over the manifest
* setting.
* </UL>
* <p>
* The {@code SplashScreen} class provides the API for controlling the splash
* screen. This class may be used to close the splash screen, change the splash
* screen image, get the image position/size and paint in the splash screen. It
* cannot be used to create the splash screen; you should use the command line or manifest
* file option for that.
* <p>
* This class cannot be instantiated. Only a single instance of this class
* can exist, and it may be obtained using the {@link #getSplashScreen()}
* static method. In case the splash screen has not been created at
* application startup via the command line or manifest file option,
* the <code>getSplashScreen</code> method returns <code>null</code>.
*
* @author Oleg Semenov
* @since 1.6
*/
public final class SplashScreen {
SplashScreen(long ptr) { // non-public constructor
splashPtr = ptr;
wasClosed = false;
}
/**
* Returns the {@code SplashScreen} object used for
* Java startup splash screen control.
*
* @throws UnsupportedOperationException if the splash screen feature is not
* supported by the current toolkit
* @throws HeadlessException if {@code GraphicsEnvironment.isHeadless()}
* returns true
* @return the {@link SplashScreen} instance, or <code>null</code> if there is
* none or it has already been closed
*/
public static synchronized SplashScreen getSplashScreen() {
if (GraphicsEnvironment.isHeadless()) {
throw new HeadlessException();
}
// SplashScreen class is now a singleton
if (SplashScreen.theInstance == null) {
java.security.AccessController.doPrivileged(
new sun.security.action.LoadLibraryAction("splashscreen"));
long ptr = _getInstance();
if (ptr == 0) {
return null;
}
if (!_isVisible(ptr)) {
return null;
}
SplashScreen.theInstance = new SplashScreen(ptr);
}
return (theInstance.isVisible() ? theInstance : null);
}
/**
* Changes the splash screen image. The new image is loaded from the
* specified URL; GIF, JPEG and PNG image formats are supported.
* The method returns after the image has finished loading and the window
* has been updated.
* The splash screen window is resized according to the size of
* the image and is centered on the screen.
*
* @param imageURL the non-<code>null</code> URL for the new
* splash screen image
* @throws NullPointerException if {@code imageURL} is <code>null</code>
* @throws IOException if there was an error while loading the image
* @throws IllegalStateException if the splash screen has already been
* closed
*/
public void setImageURL(URL imageURL) throws NullPointerException, IOException, IllegalStateException {
checkVisible();
URLConnection connection = imageURL.openConnection();
connection.connect();
int length = connection.getContentLength();
java.io.InputStream stream = connection.getInputStream();
byte[] buf = new byte[length];
int off = 0;
while(true) {
// check for available data
int available = stream.available();
if (available <= 0) {
// no data available... well, let's try reading one byte
// we'll see what happens then
available = 1;
}
// check for enough room in buffer, realloc if needed
// the buffer always grows in size 2x minimum
if (off + available > length) {
length = off*2;
if (off + available > length) {
length = available+off;
}
byte[] oldBuf = buf;
buf = new byte[length];
System.arraycopy(oldBuf, 0, buf, 0, off);
}
// now read the data
int result = stream.read(buf, off, available);
if (result < 0) {
break;
}
off += result;
}
synchronized(this) {
if (!_setImageData(splashPtr, buf)) {
throw new IOException("Bad image format or i/o error when loading image");
}
this.imageURL = imageURL;
}
}
private void checkVisible() {
if (!isVisible()) {
throw new IllegalStateException("no splash screen available");
}
}
/**
* Returns the current splash screen image.
*
* @return URL for the current splash screen image file
* @throws IllegalStateException if the splash screen has already been closed
*/
public synchronized URL getImageURL() throws IllegalStateException {
checkVisible();
if (imageURL == null) {
try {
String fileName = _getImageFileName(splashPtr);
String jarName = _getImageJarName(splashPtr);
if (fileName != null) {
if (jarName != null) {
imageURL = new URL("jar:"+(new File(jarName).toURL().toString())+"!/"+fileName);
} else {
imageURL = new File(fileName).toURL();
}
}
}
catch(java.net.MalformedURLException e) {
// we'll just return null in this case
}
}
return imageURL;
}
/**
* Returns the bounds of the splash screen window as a {@link Rectangle}.
* This may be useful if, for example, you want to replace the splash
* screen with your window at the same location.
* <p>
* You cannot control the size or position of the splash screen.
* The splash screen size is adjusted automatically when the image changes.
*
* @return a {@code Rectangle} containing the splash screen bounds
* @throws IllegalStateException if the splash screen has already been closed
*/
public Rectangle getBounds() throws IllegalStateException {
checkVisible();
return _getBounds(splashPtr);
}
/**
* Returns the size of the splash screen window as a {@link Dimension}.
* This may be useful if, for example,
* you want to draw on the splash screen overlay surface.
* <p>
* You cannot control the size or position of the splash screen.
* The splash screen size is adjusted automatically when the image changes.
*
* @return a {@link Dimension} object indicating the splash screen size
* @throws IllegalStateException if the splash screen has already been closed
*/
public Dimension getSize() throws IllegalStateException {
return getBounds().getSize();
}
/**
* Creates a graphics context (as a {@link Graphics2D} object) for the splash
* screen overlay image, which allows you to draw over the splash screen.
* Note that you do not draw on the main image but on the image that is
* displayed over the main image using alpha blending. Also note that drawing
* on the overlay image does not necessarily update the contents of splash
* screen window. You should call {@code update()} on the
* <code>SplashScreen</code> when you want the splash screen to be
* updated immediately.
*
* @return graphics context for the splash screen overlay surface
* @throws IllegalStateException if the splash screen has already been closed
*/
public Graphics2D createGraphics() throws IllegalStateException {
if (image==null) {
Dimension dim = getSize();
image = new BufferedImage(dim.width, dim.height, BufferedImage.TYPE_INT_ARGB);
}
return image.createGraphics();
}
/**
* Updates the splash window with current contents of the overlay image.
*
* @throws IllegalStateException if the overlay image does not exist;
* for example, if {@code createGraphics} has never been called,
* or if the splash screen has already been closed
*/
public void update() throws IllegalStateException {
checkVisible();
if (image == null) {
throw new IllegalStateException("no overlay image available");
}
DataBuffer buf = image.getRaster().getDataBuffer();
if (!(buf instanceof DataBufferInt)) {
throw new AssertionError("Overlay image DataBuffer is of invalid type == "+buf.getClass().getName());
}
int numBanks = buf.getNumBanks();
if (numBanks!=1) {
throw new AssertionError("Invalid number of banks =="+numBanks+" in overlay image DataBuffer");
}
if (!(image.getSampleModel() instanceof SinglePixelPackedSampleModel)) {
throw new AssertionError("Overlay image has invalid sample model == "+image.getSampleModel().getClass().getName());
}
SinglePixelPackedSampleModel sm = (SinglePixelPackedSampleModel)image.getSampleModel();
int scanlineStride = sm.getScanlineStride();
Rectangle rect = image.getRaster().getBounds();
int[] data = ((DataBufferInt)buf).getData();
_update(splashPtr, data, rect.x, rect.y, rect.width, rect.height, scanlineStride);
}
/**
* Hides the splash screen, closes the window, and releases all associated
* resources.
*
* @throws IllegalStateException if the splash screen has already been closed
*/
public synchronized void close() throws IllegalStateException {
checkVisible();
_close(splashPtr);
image = null;
wasClosed = true;
// There should be resetting the theInstance to null to prevent memory
// leak. But it brings some more problems with the bug 6382748, so we
// let the limited leak to stay.
}
/**
* Determines whether the splash screen is visible. The splash screen may
* be hidden using {@link #close()}, it is also hidden automatically when
* the first AWT/Swing window is made visible.
*
* @return true if the splash screen is visible (has not been closed yet),
* false otherwise
*/
public boolean isVisible() {
return !wasClosed && _isVisible(splashPtr);
}
private BufferedImage image; // overlay image
private long splashPtr; // pointer to native Splash structure
private boolean wasClosed;
private URL imageURL;
/**
* The instance reference for the singleton.
* (<code>null</code> if no instance exists yet.)
*
* @see #getSplashScreen
* @see #close
*/
private static SplashScreen theInstance = null;
private native static void _update(long splashPtr, int[] data, int x, int y, int width, int height, int scanlineStride);
private native static boolean _isVisible(long splashPtr);
private native static Rectangle _getBounds(long splashPtr);
private native static long _getInstance();
private native static void _close(long splashPtr);
private native static String _getImageFileName(long splashPtr);
private native static String _getImageJarName(long SplashPtr);
private native static boolean _setImageData(long SplashPtr, byte[] data);
};
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