| /* |
| * Copyright (c) 1999, 2007, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package javax.imageio.spi; |
| |
| import java.security.PrivilegedAction; |
| import java.security.AccessController; |
| import java.util.HashMap; |
| import java.util.Iterator; |
| import java.util.Map; |
| import java.util.NoSuchElementException; |
| import java.util.Set; |
| import java.util.Vector; |
| import com.sun.imageio.spi.FileImageInputStreamSpi; |
| import com.sun.imageio.spi.FileImageOutputStreamSpi; |
| import com.sun.imageio.spi.InputStreamImageInputStreamSpi; |
| import com.sun.imageio.spi.OutputStreamImageOutputStreamSpi; |
| import com.sun.imageio.spi.RAFImageInputStreamSpi; |
| import com.sun.imageio.spi.RAFImageOutputStreamSpi; |
| import com.sun.imageio.plugins.gif.GIFImageReaderSpi; |
| import com.sun.imageio.plugins.gif.GIFImageWriterSpi; |
| import com.sun.imageio.plugins.jpeg.JPEGImageReaderSpi; |
| import com.sun.imageio.plugins.jpeg.JPEGImageWriterSpi; |
| import com.sun.imageio.plugins.png.PNGImageReaderSpi; |
| import com.sun.imageio.plugins.png.PNGImageWriterSpi; |
| import com.sun.imageio.plugins.bmp.BMPImageReaderSpi; |
| import com.sun.imageio.plugins.bmp.BMPImageWriterSpi; |
| import com.sun.imageio.plugins.wbmp.WBMPImageReaderSpi; |
| import com.sun.imageio.plugins.wbmp.WBMPImageWriterSpi; |
| import sun.awt.AppContext; |
| import java.util.ServiceLoader; |
| import java.util.ServiceConfigurationError; |
| |
| /** |
| * A registry for service provider instances. Service provider |
| * classes may be detected at run time by means of meta-information in |
| * the JAR files containing them. The intent is that it be relatively |
| * inexpensive to load and inspect all available service provider |
| * classes. These classes may them be used to locate and instantiate |
| * more heavyweight classes that will perform actual work, in this |
| * case instances of <code>ImageReader</code>, |
| * <code>ImageWriter</code>, <code>ImageTranscoder</code>, |
| * <code>ImageInputStream</code>, and <code>ImageOutputStream</code>. |
| * |
| * <p> Service providers found on the system classpath (<i>e.g.</i>, |
| * the <code>jre/lib/ext</code> directory in Sun's implementation of |
| * JDK) are automatically loaded as soon as this class is |
| * instantiated. |
| * |
| * <p> When the <code>registerApplicationClasspathSpis</code> method |
| * is called, service provider instances declared in the |
| * meta-information section of JAR files on the application class path |
| * are loaded. To declare a service provider, a <code>services</code> |
| * subdirectory is placed within the <code>META-INF</code> directory |
| * that is present in every JAR file. This directory contains a file |
| * for each service provider interface that has one or more |
| * implementation classes present in the JAR file. For example, if |
| * the JAR file contained a class named |
| * <code>com.mycompany.imageio.MyFormatReaderSpi</code> which |
| * implements the <code>ImageReaderSpi</code> interface, the JAR file |
| * would contain a file named: |
| * |
| * <pre> |
| * META-INF/services/javax.imageio.spi.ImageReaderSpi |
| * </pre> |
| * |
| * containing the line: |
| * |
| * <pre> |
| * com.mycompany.imageio.MyFormatReaderSpi |
| * </pre> |
| * |
| * <p> The service provider classes are intended to be lightweight |
| * and quick to load. Implementations of these interfaces |
| * should avoid complex dependencies on other classes and on |
| * native code. |
| * |
| * <p> It is also possible to manually add service providers not found |
| * automatically, as well as to remove those that are using the |
| * interfaces of the <code>ServiceRegistry</code> class. Thus |
| * the application may customize the contents of the registry as it |
| * sees fit. |
| * |
| * <p> For more details on declaring service providers, and the JAR |
| * format in general, see the <a |
| * href="{@docRoot}/../technotes/guides/jar/jar.html"> |
| * JAR File Specification</a>. |
| * |
| */ |
| public final class IIORegistry extends ServiceRegistry { |
| |
| /** |
| * A <code>Vector</code> containing the valid IIO registry |
| * categories (superinterfaces) to be used in the constructor. |
| */ |
| private static final Vector initialCategories = new Vector(5); |
| |
| static { |
| initialCategories.add(ImageReaderSpi.class); |
| initialCategories.add(ImageWriterSpi.class); |
| initialCategories.add(ImageTranscoderSpi.class); |
| initialCategories.add(ImageInputStreamSpi.class); |
| initialCategories.add(ImageOutputStreamSpi.class); |
| } |
| |
| /** |
| * Set up the valid service provider categories and automatically |
| * register all available service providers. |
| * |
| * <p> The constructor is private in order to prevent creation of |
| * additional instances. |
| */ |
| private IIORegistry() { |
| super(initialCategories.iterator()); |
| registerStandardSpis(); |
| registerApplicationClasspathSpis(); |
| } |
| |
| /** |
| * Returns the default <code>IIORegistry</code> instance used by |
| * the Image I/O API. This instance should be used for all |
| * registry functions. |
| * |
| * <p> Each <code>ThreadGroup</code> will receive its own |
| * instance; this allows different <code>Applet</code>s in the |
| * same browser (for example) to each have their own registry. |
| * |
| * @return the default registry for the current |
| * <code>ThreadGroup</code>. |
| */ |
| public static IIORegistry getDefaultInstance() { |
| AppContext context = AppContext.getAppContext(); |
| IIORegistry registry = |
| (IIORegistry)context.get(IIORegistry.class); |
| if (registry == null) { |
| // Create an instance for this AppContext |
| registry = new IIORegistry(); |
| context.put(IIORegistry.class, registry); |
| } |
| return registry; |
| } |
| |
| private void registerStandardSpis() { |
| // Hardwire standard SPIs |
| registerServiceProvider(new GIFImageReaderSpi()); |
| registerServiceProvider(new GIFImageWriterSpi()); |
| registerServiceProvider(new BMPImageReaderSpi()); |
| registerServiceProvider(new BMPImageWriterSpi()); |
| registerServiceProvider(new WBMPImageReaderSpi()); |
| registerServiceProvider(new WBMPImageWriterSpi()); |
| registerServiceProvider(new PNGImageReaderSpi()); |
| registerServiceProvider(new PNGImageWriterSpi()); |
| registerServiceProvider(new JPEGImageReaderSpi()); |
| registerServiceProvider(new JPEGImageWriterSpi()); |
| registerServiceProvider(new FileImageInputStreamSpi()); |
| registerServiceProvider(new FileImageOutputStreamSpi()); |
| registerServiceProvider(new InputStreamImageInputStreamSpi()); |
| registerServiceProvider(new OutputStreamImageOutputStreamSpi()); |
| registerServiceProvider(new RAFImageInputStreamSpi()); |
| registerServiceProvider(new RAFImageOutputStreamSpi()); |
| |
| registerInstalledProviders(); |
| } |
| |
| /** |
| * Registers all available service providers found on the |
| * application class path, using the default |
| * <code>ClassLoader</code>. This method is typically invoked by |
| * the <code>ImageIO.scanForPlugins</code> method. |
| * |
| * @see javax.imageio.ImageIO#scanForPlugins |
| * @see ClassLoader#getResources |
| */ |
| public void registerApplicationClasspathSpis() { |
| // FIX: load only from application classpath |
| |
| ClassLoader loader = Thread.currentThread().getContextClassLoader(); |
| |
| Iterator categories = getCategories(); |
| while (categories.hasNext()) { |
| Class<IIOServiceProvider> c = (Class)categories.next(); |
| Iterator<IIOServiceProvider> riter = |
| ServiceLoader.load(c, loader).iterator(); |
| while (riter.hasNext()) { |
| try { |
| // Note that the next() call is required to be inside |
| // the try/catch block; see 6342404. |
| IIOServiceProvider r = riter.next(); |
| registerServiceProvider(r); |
| } catch (ServiceConfigurationError err) { |
| if (System.getSecurityManager() != null) { |
| // In the applet case, we will catch the error so |
| // registration of other plugins can proceed |
| err.printStackTrace(); |
| } else { |
| // In the application case, we will throw the |
| // error to indicate app/system misconfiguration |
| throw err; |
| } |
| } |
| } |
| } |
| } |
| |
| private void registerInstalledProviders() { |
| /* |
| We need load installed providers from lib/ext |
| directory in the privileged mode in order to |
| be able read corresponding jar files even if |
| file read capability is restricted (like the |
| applet context case). |
| */ |
| PrivilegedAction doRegistration = |
| new PrivilegedAction() { |
| public Object run() { |
| Iterator categories = getCategories(); |
| while (categories.hasNext()) { |
| Class<IIOServiceProvider> c = (Class)categories.next(); |
| for (IIOServiceProvider p : ServiceLoader.loadInstalled(c)) { |
| registerServiceProvider(p); |
| } |
| } |
| return this; |
| } |
| }; |
| |
| AccessController.doPrivileged(doRegistration); |
| } |
| } |
