org.apache.xmlgraphics.image.loader.spi.ImageLoaderFactory Maven / Gradle / Ivy
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* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/* $Id: ImageLoaderFactory.java 924666 2010-03-18 08:26:30Z jeremias $ */
package org.apache.xmlgraphics.image.loader.spi;
import org.apache.xmlgraphics.image.loader.ImageFlavor;
import org.apache.xmlgraphics.image.loader.ImageInfo;
/**
* This interface is implemented to provide information about an ImageLoader and to create new
* instances. A separate factory allows implementation to dynamically detect if the underlying
* libraries are available in the classpath so the caller can skip this implementation if it's
* not functional.
*/
public interface ImageLoaderFactory {
/**
* Returns an array of MIME types supported by this implementation.
* @return the MIME type array
*/
String[] getSupportedMIMETypes();
/**
* Returns an array of ImageFlavors that are supported by this implementation for a given
* MIME type.
* @param mime the MIME type
* @return the ImageFlavor array
*/
ImageFlavor[] getSupportedFlavors(String mime);
/**
* Indicates whether the given image (represented by an {@link ImageInfo} object) is supported
* by the loader. By default, implementations return true assuming all images of the supported
* MIME types can be processed correctly. In some cases, however, an ImageLoader may only
* support a subset of a format because it offers an optimized way to embed the image in
* the target format (for example: CCITT compressed TIFF files in PDF and PostScript). For
* this to work, the preloader must register some information in the ImageInfo's custom
* objects so the factory can identify if an image may or may not be supported.
* @param imageInfo the image info object
* @return true if the image is supported by the loaders generated by this factory
*/
boolean isSupported(ImageInfo imageInfo);
/**
* Creates and returns a new ImageLoader instance.
* @param targetFlavor the target image flavor to produce
* @return a new ImageLoader instance
*/
ImageLoader newImageLoader(ImageFlavor targetFlavor);
/**
* Returns the usage penalty for a particular ImageLoader. This is used to select the best
* ImageLoader implementation for loading an image.
* @param mime the MIME type
* @param flavor the target image flavor
* @return the usage penalty (must be a non-negative integer)
* @deprecated Redundancy with {@link ImageLoader#getUsagePenalty()}
*/
int getUsagePenalty(String mime, ImageFlavor flavor);
/**
* Indicates whether the underlying libraries needed by the implementation are available.
* @return true if the implementation is functional.
*/
boolean isAvailable();
}