| /* ImageInputStreamSpi.java -- Service provider for image input streams. |
| Copyright (C) 2004, 2005 Free Software Foundation, Inc. |
| |
| This file is part of GNU Classpath. |
| |
| GNU Classpath is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2, or (at your option) |
| any later version. |
| |
| GNU Classpath 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 for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GNU Classpath; see the file COPYING. If not, write to the |
| Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
| 02110-1301 USA. |
| |
| Linking this library statically or dynamically with other modules is |
| making a combined work based on this library. Thus, the terms and |
| conditions of the GNU General Public License cover the whole |
| combination. |
| |
| As a special exception, the copyright holders of this library give you |
| permission to link this library with independent modules to produce an |
| executable, regardless of the license terms of these independent |
| modules, and to copy and distribute the resulting executable under |
| terms of your choice, provided that you also meet, for each linked |
| independent module, the terms and conditions of the license of that |
| module. An independent module is a module which is not derived from |
| or based on this library. If you modify this library, you may extend |
| this exception to your version of the library, but you are not |
| obligated to do so. If you do not wish to do so, delete this |
| exception statement from your version. */ |
| |
| |
| package javax.imageio.spi; |
| |
| import java.io.File; |
| import java.io.IOException; |
| |
| import javax.imageio.stream.ImageInputStream; |
| |
| /** |
| * An abstract superclass for service providers that create |
| * {@linkplain javax.imageio.stream.ImageInputStream image input |
| * streams} for a file, URL, byte array or any other source. |
| * |
| * @since 1.4 |
| * |
| * @author Sascha Brawer (brawer@dandelis.ch) |
| */ |
| public abstract class ImageInputStreamSpi |
| extends IIOServiceProvider |
| { |
| /** |
| * Indicates which kind of input is processable by the streams |
| * created by {@link #createInputStreamInstance(Object)}. |
| */ |
| protected Class inputClass; |
| |
| |
| /** |
| * Constructs a service provider for image input streams, given no |
| * parameters. It is up to the sub-class to set {@link #vendorName}, |
| * {@link #version} and {@link #inputClass} to non-null values. |
| */ |
| protected ImageInputStreamSpi() |
| { |
| } |
| |
| |
| /** |
| * Constructs a service provider for image input streams, given the |
| * vendor name and a version string. |
| * |
| * @throws IllegalArgumentException if <code>vendorName</code> |
| * or <code>version</code> is <code>null</code>. |
| */ |
| public ImageInputStreamSpi(String vendorName, String version, |
| Class inputClass) |
| { |
| super(vendorName, version); |
| this.inputClass = inputClass; |
| } |
| |
| |
| /** |
| * Determines which kind of input is processable by the streams |
| * created by {@link #createInputStreamInstance(Object)}. |
| */ |
| public Class getInputClass() |
| { |
| return inputClass; |
| } |
| |
| |
| /** |
| * Determines whether <code>ImageInputStreams</code> created |
| * by this service provider benefit from using a cache file. |
| * |
| * <p>The default behavior is to return <code>false</code>. |
| * |
| * @return <code>true</code> if the created streams are faster or |
| * need less memory when a cache file is being used; |
| * <code>false</code> if no positive effect results from the cache |
| * file. |
| */ |
| public boolean canUseCacheFile() |
| { |
| return false; |
| } |
| |
| |
| /** |
| * Determines whether <code>ImageInputStreams</code> created |
| * by this service provider require the use of a cache file. |
| * |
| * <p>The default behavior is to return <code>false</code>. |
| * |
| * @return <code>true</code> if the created streams can only work |
| * when a cache file is being used; <code>false</code> if no cache |
| * file is needed. |
| */ |
| public boolean needsCacheFile() |
| { |
| return false; |
| } |
| |
| |
| public abstract ImageInputStream createInputStreamInstance(Object input, |
| boolean useCache, |
| File cacheDir) |
| throws IOException; |
| |
| |
| public ImageInputStream createInputStreamInstance(Object input) |
| throws IOException |
| { |
| return createInputStreamInstance(input, canUseCacheFile(), null); |
| } |
| } |