1 files changed, 85 insertions, 0 deletions
diff --git a/infra/translate-impl/src/main/java/io/fd/honeycomb/translate/impl/write/registry/SubtreeWriter.java b/infra/translate-impl/src/main/java/io/fd/honeycomb/translate/impl/write/registry/SubtreeWriter.java
new file mode 100644
index 000000000..fc6ecc67e
--- /dev/null
+++ b/infra/translate-impl/src/main/java/io/fd/honeycomb/translate/impl/write/registry/SubtreeWriter.java
@@ -0,0 +1,85 @@
+/*
+ * Copyright (c) 2016 Cisco and/or its affiliates.
+ *
+ * Licensed 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 io.fd.honeycomb.translate.impl.write.registry;
+
+import static com.google.common.base.Preconditions.checkArgument;
+
+import com.google.common.collect.Iterables;
+import io.fd.honeycomb.translate.write.WriteContext;
+import io.fd.honeycomb.translate.write.WriteFailedException;
+import io.fd.honeycomb.translate.write.Writer;
+import java.util.HashSet;
+import java.util.Set;
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+import org.opendaylight.yangtools.yang.binding.DataObject;
+import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
+
+/**
+ * Simple writer delegate for subtree writers (writers handling also children nodes) providing a list of all the
+ * children nodes being handled.
+ */
+final class SubtreeWriter<D extends DataObject> implements Writer<D> {
+
+    private final Writer<D> delegate;
+    private final Set<InstanceIdentifier<?>> handledChildTypes = new HashSet<>();
+
+    private SubtreeWriter(final Writer<D> delegate, Set<InstanceIdentifier<?>> handledTypes) {
+        this.delegate = delegate;
+        for (InstanceIdentifier<?> handledType : handledTypes) {
+            // Iid has to start with writer's handled root type
+            checkArgument(delegate.getManagedDataObjectType().getTargetType().equals(
+                    handledType.getPathArguments().iterator().next().getType()),
+                    "Handled node from subtree has to be identified by an instance identifier starting from: %s."
+                    + "Instance identifier was: %s", getManagedDataObjectType().getTargetType(), handledType);
+            checkArgument(Iterables.size(handledType.getPathArguments()) > 1,
+                    "Handled node from subtree identifier too short: %s", handledType);
+            handledChildTypes.add(InstanceIdentifier.create(Iterables.concat(
+                    getManagedDataObjectType().getPathArguments(), Iterables.skip(handledType.getPathArguments(), 1))));
+        }
+    }
+
+    /**
+     * Return set of types also handled by this writer. All of the types are children of the type managed by this
+     * writer excluding the type of this writer.
+     */
+    Set<InstanceIdentifier<?>> getHandledChildTypes() {
+        return handledChildTypes;
+    }
+
+    @Override
+    public void update(
+            @Nonnull final InstanceIdentifier<? extends DataObject> id,
+            @Nullable final DataObject dataBefore,
+            @Nullable final DataObject dataAfter, @Nonnull final WriteContext ctx) throws WriteFailedException {
+        delegate.update(id, dataBefore, dataAfter, ctx);
+    }
+
+    @Override
+    @Nonnull
+    public InstanceIdentifier<D> getManagedDataObjectType() {
+        return delegate.getManagedDataObjectType();
+    }
+
+    /**
+     * Wrap a writer as a subtree writer.
+     */
+    static Writer<?> createForWriter(@Nonnull final Set<InstanceIdentifier<?>> handledChildren,
+                                     @Nonnull final Writer<? extends DataObject> writer) {
+        return new SubtreeWriter<>(writer, handledChildren);
+    }
+}