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diff --git a/sca-java-1.x/branches/sca-java-integration/sca/kernel/core/src/main/java/org/apache/tuscany/core/databinding/impl/MediatorImpl.java b/sca-java-1.x/branches/sca-java-integration/sca/kernel/core/src/main/java/org/apache/tuscany/core/databinding/impl/MediatorImpl.java
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+++ b/sca-java-1.x/branches/sca-java-integration/sca/kernel/core/src/main/java/org/apache/tuscany/core/databinding/impl/MediatorImpl.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.core.databinding.impl;
+
+import java.util.List;
+import java.util.Map;
+
+import org.apache.tuscany.spi.annotation.Autowire;
+import org.apache.tuscany.spi.databinding.DataBindingRegistry;
+import org.apache.tuscany.spi.databinding.DataPipe;
+import org.apache.tuscany.spi.databinding.Mediator;
+import org.apache.tuscany.spi.databinding.PullTransformer;
+import org.apache.tuscany.spi.databinding.PushTransformer;
+import org.apache.tuscany.spi.databinding.TransformationContext;
+import org.apache.tuscany.spi.databinding.TransformationException;
+import org.apache.tuscany.spi.databinding.Transformer;
+import org.apache.tuscany.spi.databinding.TransformerRegistry;
+import org.apache.tuscany.spi.model.DataType;
+import org.osoa.sca.annotations.Scope;
+
+/**
+ * Default Mediator implementation
+ */
+@Scope("COMPOSITE")
+public class MediatorImpl implements Mediator {
+
+    private DataBindingRegistry dataBindingRegistry;
+
+    private TransformerRegistry transformerRegistry;
+
+    @Autowire
+    public void setTransformerRegistry(TransformerRegistry transformerRegistry) {
+        this.transformerRegistry = transformerRegistry;
+    }
+
+    /**
+     * @param dataBindingRegistry the dataBindingRegistry to set
+     */
+    @Autowire
+    public void setDataBindingRegistry(DataBindingRegistry dataBindingRegistry) {
+        this.dataBindingRegistry = dataBindingRegistry;
+    }
+
+    /**
+     * @see org.apache.tuscany.spi.databinding.Mediator#mediate(java.lang.Object,
+     *      org.apache.tuscany.spi.model.DataType,
+     *      org.apache.tuscany.spi.model.DataType, Map)
+     */
+    @SuppressWarnings("unchecked")
+    public Object mediate(Object source,
+                          DataType sourceDataType,
+                          DataType targetDataType,
+                          Map<Class<?>, Object> metadata) {
+        if (sourceDataType == null) {
+            sourceDataType = dataBindingRegistry.introspectType(source);
+        }
+        if (sourceDataType == null) {
+            return source;
+        } else if (sourceDataType.equals(targetDataType)) {
+            return source;
+        }
+
+        List<Transformer> path = getTransformerChain(sourceDataType, targetDataType);
+
+        Object result = source;
+        int size = path.size();
+        int i = 0;
+        while (i < size) {
+            Transformer transformer = path.get(i);
+            TransformationContext context =
+                createTransformationContext(sourceDataType, targetDataType, size, i, transformer, metadata);
+            // the source and target type
+            if (transformer instanceof PullTransformer) {
+                // For intermediate node, set data type to null
+                result = ((PullTransformer)transformer).transform(result, context);
+            } else if (transformer instanceof PushTransformer) {
+                DataPipe dataPipe = (i < size - 1) ? (DataPipe)path.get(++i) : null;
+                ((PushTransformer)transformer).transform(result, dataPipe.getSink(), context);
+                result = dataPipe.getResult();
+            }
+            i++;
+        }
+
+        return result;
+    }
+
+    private TransformationContext createTransformationContext(DataType sourceDataType,
+                                                              DataType targetDataType,
+                                                              int size,
+                                                              int index,
+                                                              Transformer transformer,
+                                                              Map<Class<?>, Object> metadata) {
+        DataType sourceType =
+            (index == 0) ? sourceDataType : new DataType<Object>(transformer.getSourceDataBinding(),
+                                                                 Object.class, null);
+        DataType targetType =
+            (index == size - 1) ? targetDataType : new DataType<Object>(transformer.getTargetDataBinding(),
+                                                                        Object.class, null);
+        ClassLoader classLoader = Thread.currentThread().getContextClassLoader();
+        TransformationContext context =
+            new TransformationContextImpl(sourceType, targetType, classLoader, metadata);
+        return context;
+    }
+
+    @SuppressWarnings("unchecked")
+    public void mediate(Object source,
+                        Object target,
+                        DataType sourceDataType,
+                        DataType targetDataType,
+                        Map<Class<?>, Object> metadata) {
+        if (source == null) {
+            // Shortcut for null value
+            return;
+        }
+        if (sourceDataType == null) {
+            sourceDataType = dataBindingRegistry.introspectType(source);
+        }
+        if (sourceDataType == null) {
+            return;
+        } else if (sourceDataType.equals(targetDataType)) {
+            return;
+        }
+
+        List<Transformer> path = getTransformerChain(sourceDataType, targetDataType);
+        Object result = source;
+        int size = path.size();
+        for (int i = 0; i < size; i++) {
+            Transformer transformer = path.get(i);
+            TransformationContext context =
+                createTransformationContext(sourceDataType, targetDataType, size, i, transformer, metadata);
+
+            if (transformer instanceof PullTransformer) {
+                result = ((PullTransformer)transformer).transform(result, context);
+            } else if (transformer instanceof PushTransformer) {
+                DataPipe dataPipe = (i < size - 1) ? (DataPipe)path.get(++i) : null;
+                Object sink = dataPipe != null ? dataPipe.getSink() : target;
+                ((PushTransformer)transformer).transform(result, sink, context);
+                result = (dataPipe != null) ? dataPipe.getResult() : null;
+            }
+        }
+    }
+
+    private List<Transformer> getTransformerChain(DataType sourceDataType, DataType targetDataType) {
+        String sourceId = sourceDataType.getDataBinding();
+        String targetId = targetDataType.getDataBinding();
+        List<Transformer> path = transformerRegistry.getTransformerChain(sourceId, targetId);
+        if (path == null) {
+            TransformationException ex = new TransformationException("No path found for the transformation");
+            ex.addContextName("Source: " + sourceId);
+            ex.addContextName("Target: " + targetId);
+            throw ex;
+        }
+        return path;
+    }
+
+    /**
+     * @return the dataBindingRegistry
+     */
+    public DataBindingRegistry getDataBindingRegistry() {
+        return dataBindingRegistry;
+    }
+
+    /**
+     * @return the transformerRegistry
+     */
+    public TransformerRegistry getTransformerRegistry() {
+        return transformerRegistry;
+    }
+}