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diff --git a/sca-java-1.x/branches/sca-java-0.99/modules/databinding/src/main/java/org/apache/tuscany/sca/databinding/DefaultTransformerExtensionPoint.java b/sca-java-1.x/branches/sca-java-0.99/modules/databinding/src/main/java/org/apache/tuscany/sca/databinding/DefaultTransformerExtensionPoint.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.    
+ */
+package org.apache.tuscany.sca.databinding;
+
+import java.io.IOException;
+import java.lang.ref.WeakReference;
+import java.lang.reflect.Constructor;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Map;
+
+import org.apache.tuscany.sca.databinding.impl.DirectedGraph;
+import org.apache.tuscany.sca.databinding.impl.ServiceConfigurationUtil;
+
+/**
+ * @version $Rev$ $Date$
+ */
+public class DefaultTransformerExtensionPoint implements TransformerExtensionPoint {
+    private boolean loadedTransformers;
+    
+    private final DirectedGraph<Object, Transformer> graph = new DirectedGraph<Object, Transformer>();
+    
+    public DefaultTransformerExtensionPoint() {
+    }
+    
+    public void addTransformer(String sourceType, String resultType, int weight, Transformer transformer) {
+        graph.addEdge(sourceType, resultType, transformer, weight);
+    }
+
+    public void addTransformer(Transformer transformer) {
+        graph.addEdge(transformer.getSourceDataBinding(),
+            transformer.getTargetDataBinding(),
+            transformer,
+            transformer.getWeight());
+    }
+
+    public boolean removeTransformer(String sourceType, String resultType) {
+        return graph.removeEdge(sourceType, resultType);
+    }
+
+    public Transformer getTransformer(String sourceType, String resultType) {
+        loadTransformers();
+        
+        DirectedGraph<Object, Transformer>.Edge edge = graph.getEdge(sourceType, resultType);
+        return (edge == null) ? null : edge.getValue();
+    }
+
+    /**
+     * Dynamically load transformers registered under META-INF/services.
+     *
+     */
+    private void loadTransformers() {
+        if (loadedTransformers) {
+            return;
+        }
+        loadTransformers(PullTransformer.class);
+        loadTransformers(PushTransformer.class);
+        loadedTransformers = true;
+    }
+
+    /**
+     * Dynamically load transformers registered under META-INF/services.
+     * 
+     * @param transformerClass
+     */
+    private void loadTransformers(Class<?> transformerClass) {
+
+        // Get the transformer service declarations
+        ClassLoader classLoader = transformerClass.getClassLoader();
+        List<String> transformerDeclarations; 
+        try {
+            transformerDeclarations = ServiceConfigurationUtil.getServiceClassNames(classLoader, transformerClass.getName());
+        } catch (IOException e) {
+            throw new IllegalStateException(e);
+        }
+        
+        // Load transformers
+        for (String transformerDeclaration: transformerDeclarations) {
+            Map<String, String> attributes = ServiceConfigurationUtil.parseServiceDeclaration(transformerDeclaration);
+            String className = attributes.get("class");
+            String source = attributes.get("source");
+            String target = attributes.get("target");
+            int weight = Integer.valueOf(attributes.get("weight"));
+                
+            // Create a transformer wrapper and register it
+            Transformer transformer;
+            if (transformerClass == PullTransformer.class) {
+                transformer = new LazyPullTransformer(source, target, weight, classLoader, className);
+            } else {
+                transformer = new LazyPushTransformer(source, target, weight, classLoader, className);
+            }
+            addTransformer(transformer);
+        }
+    }
+    
+    /**
+     * A transformer facade allowing transformers to be lazily loaded
+     * and initialized.
+     */
+    private static class LazyPullTransformer implements PullTransformer<Object, Object> {
+
+        private String source;
+        private String target;
+        private int weight;
+        private WeakReference<ClassLoader> classLoader;
+        private String className;
+        private PullTransformer<Object, Object> transformer;
+
+        public LazyPullTransformer(String source, String target, int weight, ClassLoader classLoader, String className) {
+            this.source = source;
+            this.target = target;
+            this.weight = weight;
+            this.classLoader = new WeakReference<ClassLoader>(classLoader);
+            this.className = className;
+        }
+
+        /**
+         * Load and instantiate the transformer class.
+         * 
+         * @return The transformer.
+         */
+        @SuppressWarnings("unchecked")
+        private PullTransformer<Object, Object> getTransformer() {
+            if (transformer == null) {
+                try {
+                    Class<PullTransformer<Object, Object>> transformerClass =
+                        (Class<PullTransformer<Object, Object>>)Class.forName(className, true, classLoader.get());
+                    Constructor<PullTransformer<Object, Object>> constructor = transformerClass.getConstructor();
+                    transformer = constructor.newInstance();
+                } catch (Exception e) {
+                    throw new IllegalStateException(e);
+                }
+            }
+            return transformer;
+        }
+
+        public String getSourceDataBinding() {
+            return source;
+        }
+
+        public String getTargetDataBinding() {
+            return target;
+        }
+
+        public int getWeight() {
+            return weight;
+        }
+        
+        public Object transform(Object source, TransformationContext context) {
+            return getTransformer().transform(source, context);
+        }
+
+    }
+
+    /**
+     * A transformer facade allowing transformers to be lazily loaded
+     * and initialized.
+     */
+    private static class LazyPushTransformer implements PushTransformer<Object, Object> {
+
+        private String source;
+        private String target;
+        private int weight;
+        private WeakReference<ClassLoader> classLoader;
+        private String className;
+        private PushTransformer<Object, Object> transformer;
+
+        public LazyPushTransformer(String source, String target, int weight, ClassLoader classLoader, String className) {
+            this.source = source;
+            this.target = target;
+            this.weight = weight;
+            this.classLoader = new WeakReference<ClassLoader>(classLoader);
+            this.className = className;
+        }
+
+        /**
+         * Load and instantiate the transformer class.
+         * 
+         * @return The transformer.
+         */
+        @SuppressWarnings("unchecked")
+        private PushTransformer<Object, Object> getTransformer() {
+            if (transformer == null) {
+                try {
+                    Class<PushTransformer<Object, Object>> transformerClass =
+                        (Class<PushTransformer<Object, Object>>)Class.forName(className, true, classLoader.get());
+                    Constructor<PushTransformer<Object, Object>> constructor = transformerClass.getConstructor();
+                    transformer = constructor.newInstance();
+                } catch (Exception e) {
+                    throw new IllegalStateException(e);
+                }
+            }
+            return transformer;
+        }
+
+        public String getSourceDataBinding() {
+            return source;
+        }
+
+        public String getTargetDataBinding() {
+            return target;
+        }
+
+        public int getWeight() {
+            return weight;
+        }
+
+        public void transform(Object source, Object sink, TransformationContext context) {
+            getTransformer().transform(source, sink, context);
+        }
+
+    }
+
+    
+    //FIXME The following methods should be on a different class from
+    // extension point
+    
+    public List<Transformer> getTransformerChain(String sourceType, String resultType) {
+        loadTransformers();
+        
+        String source = sourceType;
+        String result = resultType;
+        List<Transformer> transformers = new ArrayList<Transformer>();
+        DirectedGraph<Object, Transformer>.Path path = graph.getShortestPath(source, result);
+        if (path == null) {
+            return null;
+        }
+        for (DirectedGraph<Object, Transformer>.Edge edge : path.getEdges()) {
+            transformers.add(edge.getValue());
+        }
+        return transformers;
+    }
+
+    @Override
+    public String toString() {
+        loadTransformers();
+        
+        return graph.toString();
+    }
+
+}