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diff --git a/src/java/org/apache/fop/render/AbstractImageHandlerRegistry.java b/src/java/org/apache/fop/render/AbstractImageHandlerRegistry.java
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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.
+ */
+
+/* $Id$ */
+
+package org.apache.fop.render;
+
+import java.util.Comparator;
+import java.util.Iterator;
+import java.util.List;
+import java.util.ListIterator;
+import java.util.Map;
+
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+
+import org.apache.xmlgraphics.image.loader.Image;
+import org.apache.xmlgraphics.image.loader.ImageFlavor;
+import org.apache.xmlgraphics.util.Service;
+
+/**
+ * This class holds references to various image handlers used by the renderers. It also
+ * supports automatic discovery of additional handlers available through
+ * the class path.
+ */
+public abstract class AbstractImageHandlerRegistry {
+
+    /** the logger */
+    private static Log log = LogFactory.getLog(AbstractImageHandlerRegistry.class);
+
+    private static final Comparator HANDLER_COMPARATOR = new Comparator() {
+        public int compare(Object o1, Object o2) {
+            ImageHandlerBase h1 = (ImageHandlerBase)o1;
+            ImageHandlerBase h2 = (ImageHandlerBase)o2;
+            return h1.getPriority() - h2.getPriority();
+        }
+    };
+
+    /** Map containing image handlers for various MIME types */
+    private final Map/*<Class, ImageHandler>*/ handlers
+        = new java.util.HashMap/*<Class, ImageHandler>*/();
+
+    /** List containing the same handlers as above but ordered by priority */
+    private final List/*<ImageHandler>*/ handlerList
+        = new java.util.LinkedList/*<ImageHandler>*/();
+
+    /** Sorted Set of registered handlers */
+    private ImageFlavor[] supportedFlavors = new ImageFlavor[0];
+
+    private int handlerRegistrations;
+    private int lastSync;
+
+    /**
+     * Default constructor.
+     */
+    public AbstractImageHandlerRegistry() {
+        discoverHandlers();
+    }
+
+    /**
+     * Add an ImageHandler. The handler itself is inspected to find out what it supports.
+     * @param classname the fully qualified class name
+     */
+    public void addHandler(String classname) {
+        try {
+            ImageHandlerBase handlerInstance
+                = (ImageHandlerBase)Class.forName(classname).newInstance();
+            addHandler(handlerInstance);
+        } catch (ClassNotFoundException e) {
+            throw new IllegalArgumentException("Could not find "
+                                               + classname);
+        } catch (InstantiationException e) {
+            throw new IllegalArgumentException("Could not instantiate "
+                                               + classname);
+        } catch (IllegalAccessException e) {
+            throw new IllegalArgumentException("Could not access "
+                                               + classname);
+        } catch (ClassCastException e) {
+            throw new IllegalArgumentException(classname
+                                               + " is not an "
+                                               + getHandlerClass().getName());
+        }
+    }
+
+    /**
+     * Add an image handler. The handler itself is inspected to find out what it supports.
+     * @param handler the ImageHandler instance
+     */
+    public synchronized void addHandler(ImageHandlerBase handler) {
+        this.handlers.put(handler.getSupportedImageClass(), handler);
+
+        //Sorted insert
+        ListIterator iter = this.handlerList.listIterator();
+        while (iter.hasNext()) {
+            ImageHandlerBase h = (ImageHandlerBase)iter.next();
+            if (getHandlerComparator().compare(handler, h) < 0) {
+                iter.previous();
+                break;
+            }
+        }
+        iter.add(handler);
+        this.handlerRegistrations++;
+    }
+
+    /**
+     * Returns an ImageHandler which handles an specific image type given the MIME type
+     * of the image.
+     * @param img the Image to be handled
+     * @return the ImageHandler responsible for handling the image or null if none is available
+     */
+    public ImageHandlerBase getHandler(Image img) {
+        return getHandler(img.getClass());
+    }
+
+    /**
+     * Returns an ImageHandler which handles an specific image type given the MIME type
+     * of the image.
+     * @param imageClass the Image subclass for which to get a handler
+     * @return the ImageHandler responsible for handling the image or null if none is available
+     */
+    public synchronized ImageHandlerBase getHandler(Class imageClass) {
+        ImageHandlerBase handler = null;
+        Class cl = imageClass;
+        while (cl != null) {
+            handler = (ImageHandlerBase)handlers.get(cl);
+            if (handler != null) {
+                break;
+            }
+            cl = cl.getSuperclass();
+        }
+        return handler;
+    }
+
+    /**
+     * Returns the ordered array of supported image flavors.
+     * @return the array of image flavors
+     */
+    public synchronized ImageFlavor[] getSupportedFlavors() {
+        if (this.lastSync != this.handlerRegistrations) {
+            //Extract all ImageFlavors into a single array
+            List flavors = new java.util.ArrayList();
+            Iterator iter = this.handlerList.iterator();
+            while (iter.hasNext()) {
+                ImageFlavor[] f = ((ImageHandlerBase)iter.next()).getSupportedImageFlavors();
+                for (int i = 0; i < f.length; i++) {
+                    flavors.add(f[i]);
+                }
+            }
+            this.supportedFlavors = (ImageFlavor[])flavors.toArray(new ImageFlavor[flavors.size()]);
+            this.lastSync = this.handlerRegistrations;
+        }
+        return this.supportedFlavors;
+    }
+
+    /**
+     * Discovers ImageHandler implementations through the classpath and dynamically
+     * registers them.
+     */
+    private void discoverHandlers() {
+        // add mappings from available services
+        Class imageHandlerClass = getHandlerClass();
+        Iterator providers = Service.providers(imageHandlerClass);
+        if (providers != null) {
+            while (providers.hasNext()) {
+                ImageHandlerBase handler = (ImageHandlerBase)providers.next();
+                try {
+                    if (log.isDebugEnabled()) {
+                        log.debug("Dynamically adding ImageHandler: "
+                                + handler.getClass().getName());
+                    }
+                    addHandler(handler);
+                } catch (IllegalArgumentException e) {
+                    log.error("Error while adding ImageHandler", e);
+                }
+
+            }
+        }
+    }
+
+    /**
+     * Returns the ImageHandler comparator
+     *
+     * @return the ImageHandler comparator
+     */
+    public Comparator getHandlerComparator() {
+        return HANDLER_COMPARATOR;
+    }
+
+    /**
+     * Returns the ImageHandler implementing class
+     *
+     * @return the ImageHandler implementing class
+     */
+    public abstract Class getHandlerClass();
+}