1 files changed, 188 insertions, 0 deletions
diff --git a/tags/java/sca/2.0-M4-RC1/modules/core-databinding/src/main/java/org/apache/tuscany/sca/core/databinding/wire/DataBindingRuntimeWireProcessor.java b/tags/java/sca/2.0-M4-RC1/modules/core-databinding/src/main/java/org/apache/tuscany/sca/core/databinding/wire/DataBindingRuntimeWireProcessor.java
new file mode 100644
index 0000000000..446651c918
--- /dev/null
+++ b/tags/java/sca/2.0-M4-RC1/modules/core-databinding/src/main/java/org/apache/tuscany/sca/core/databinding/wire/DataBindingRuntimeWireProcessor.java
@@ -0,0 +1,188 @@
+/*
+ * 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.core.databinding.wire;
+
+import java.util.List;
+
+import org.apache.tuscany.sca.assembly.ComponentReference;
+import org.apache.tuscany.sca.core.ExtensionPointRegistry;
+import org.apache.tuscany.sca.core.UtilityExtensionPoint;
+import org.apache.tuscany.sca.databinding.Mediator;
+import org.apache.tuscany.sca.interfacedef.DataType;
+import org.apache.tuscany.sca.interfacedef.InterfaceContract;
+import org.apache.tuscany.sca.interfacedef.Operation;
+import org.apache.tuscany.sca.invocation.Interceptor;
+import org.apache.tuscany.sca.invocation.InvocationChain;
+import org.apache.tuscany.sca.invocation.Phase;
+import org.apache.tuscany.sca.runtime.RuntimeWire;
+import org.apache.tuscany.sca.runtime.RuntimeWireProcessor;
+
+/**
+ * This processor is responsible to add an interceptor to invocation chain if
+ * the source and target operations have different databinding requirements
+ *
+ * @version $Rev$ $Date$
+ */
+public class DataBindingRuntimeWireProcessor implements RuntimeWireProcessor {
+    private Mediator mediator;
+    
+    public DataBindingRuntimeWireProcessor(ExtensionPointRegistry registry) {
+        super();
+        this.mediator = registry.getExtensionPoint(UtilityExtensionPoint.class).getUtility(Mediator.class);
+    }
+
+    public boolean isTransformationRequired(DataType source, DataType target) {
+        if (source == null || target == null) { // void return type
+            return false;
+        }
+        if (source == target) {
+            return false;
+        }
+
+        // Output type can be null
+        if (source == null && target == null) {
+            return false;
+        } else if (source == null || target == null) {
+            return true;
+        }
+        String sourceDataBinding = source.getDataBinding();
+        String targetDataBinding = target.getDataBinding();
+        if (sourceDataBinding == targetDataBinding) {
+            return false;
+        }
+        if (sourceDataBinding == null || targetDataBinding == null) {
+            // TODO: If any of the databinding is null, then no transformation
+            return false;
+        }
+        return !sourceDataBinding.equals(targetDataBinding);
+    }
+
+    public boolean isTransformationRequired(Operation source, Operation target) {
+        if (source == target) {
+            return false;
+        }
+
+        if (source.isWrapperStyle() != target.isWrapperStyle()) {
+            return true;
+        }
+
+        // Check output type
+        DataType sourceOutputType = source.getOutputType();
+        DataType targetOutputType = target.getOutputType();
+
+        // Note the target output type is now the source for checking
+        // compatibility
+        if (isTransformationRequired(targetOutputType, sourceOutputType)) {
+            return true;
+        }
+
+        List<DataType> sourceInputType = source.getInputType().getLogical();
+        List<DataType> targetInputType = target.getInputType().getLogical();
+
+        int size = sourceInputType.size();
+        if (size != targetInputType.size()) {
+            // TUSCANY-1682: The wrapper style may have different arguments
+            return true;
+        }
+        for (int i = 0; i < size; i++) {
+            if (isTransformationRequired(sourceInputType.get(i), targetInputType.get(i))) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
+    private boolean isTransformationRequired(InterfaceContract sourceContract,
+                                             Operation sourceOperation,
+                                             InterfaceContract targetContract,
+                                             Operation targetOperation) {
+        if (targetContract == null) {
+            targetContract = sourceContract;
+        }
+        if (sourceContract == targetContract) {
+            return false;
+        }
+        return isTransformationRequired(sourceOperation, targetOperation);
+    }
+
+    public void process(RuntimeWire wire) {
+        InterfaceContract sourceContract = wire.getEndpointReference().getInterfaceContract();
+        InterfaceContract targetContract = wire.getEndpoint().getInterfaceContract();
+        if (targetContract == null) {
+            targetContract = sourceContract;
+        }
+
+        if (!sourceContract.getInterface().isRemotable()) {
+            return;
+        }
+        List<InvocationChain> chains = wire.getInvocationChains();
+        for (InvocationChain chain : chains) {
+            Operation sourceOperation = chain.getSourceOperation();
+            Operation targetOperation = chain.getTargetOperation();
+
+            Interceptor interceptor = null;
+            if (isTransformationRequired(sourceContract, sourceOperation, targetContract, targetOperation)) {
+                // Add the interceptor to the source side because multiple
+                // references can be wired to the same service
+                interceptor =
+                    new DataTransformationInterceptor(wire, sourceOperation, targetOperation, mediator);
+            } else {
+                // assume pass-by-values copies are required if interfaces are remotable and there is no data binding
+                // transformation, i.e. a transformation will result in a copy so another pass-by-value copy is unnecessary
+                if (!isOnMessage(targetOperation) && isRemotable(chain, sourceOperation, targetOperation)) {
+                    interceptor =
+                        new PassByValueInterceptor(mediator, chain, targetOperation);
+                }
+            }
+            if (interceptor != null) {
+                String phase =
+                    (wire.getEndpointReference().getReference() instanceof ComponentReference) ? Phase.REFERENCE_INTERFACE
+                        : Phase.SERVICE_INTERFACE;
+                chain.addInterceptor(phase, interceptor);
+            }
+        }
+
+    }
+
+    /**
+     * FIXME: TUSCANY-2586, temporary work around till the JIRA is fixed to prevent
+     *  the PassByValueInterceptor being used for services when the binding protocol
+     *  doesn't need the copies done.
+     */
+    protected boolean isOnMessage(Operation op) {
+        return "onMessage".equals(op.getName());
+    }
+
+    /**
+     * Pass-by-value copies are required if the interfaces are remotable unless the
+     * implementation uses the @AllowsPassByReference annotation.
+     */
+    protected boolean isRemotable(InvocationChain chain, Operation sourceOperation, Operation targetOperation) {
+        if (!sourceOperation.getInterface().isRemotable()) {
+            return false;
+        }
+        if (!targetOperation.getInterface().isRemotable()) {
+            return false;
+        }
+        return true;
+    }
+
+}