1 files changed, 72 insertions, 0 deletions
diff --git a/v3po/impl/src/main/java/io/fd/honeycomb/v3po/impl/trans/w/util/DelegatingWriterRegistry.java b/v3po/impl/src/main/java/io/fd/honeycomb/v3po/impl/trans/w/util/DelegatingWriterRegistry.java
new file mode 100644
index 000000000..6df960626
--- /dev/null
+++ b/v3po/impl/src/main/java/io/fd/honeycomb/v3po/impl/trans/w/util/DelegatingWriterRegistry.java
@@ -0,0 +1,72 @@
+/*
+ * 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.v3po.impl.trans.w.util;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+
+import com.google.common.collect.Iterables;
+import io.fd.honeycomb.v3po.impl.trans.util.VppRWUtils;
+import io.fd.honeycomb.v3po.impl.trans.w.VppWriter;
+import io.fd.honeycomb.v3po.impl.trans.w.WriteContext;
+import java.util.List;
+import java.util.Map;
+import javax.annotation.Nonnull;
+import org.opendaylight.yangtools.yang.binding.DataObject;
+import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
+
+/**
+ * Simple reader registry able to perform and aggregated read (ROOT read) on top of all
+ * provided readers. Also able to delegate a specific read to one of the delegate readers.
+ *
+ * This could serve as a utility to hold & hide all available readers in upper layers.
+ */
+public final class DelegatingWriterRegistry implements VppWriter<DataObject> {
+
+    private final Map<Class<? extends DataObject>, VppWriter<? extends DataObject>> rootReaders;
+
+    /**
+     * Create new {@link DelegatingWriterRegistry}
+     *
+     * @param rootReaders List of delegate readers
+     */
+    public DelegatingWriterRegistry(@Nonnull final List<VppWriter<? extends DataObject>> rootReaders) {
+        this.rootReaders = VppRWUtils.uniqueLinkedIndex(checkNotNull(rootReaders), VppRWUtils.MANAGER_CLASS_FUNCTION);
+    }
+
+    /**
+     * @throws UnsupportedOperationException This getter is not supported for reader registry since it does not manage a
+     *                                       specific node type
+     */
+    @Nonnull
+    @Override
+    public InstanceIdentifier<DataObject> getManagedDataObjectType() {
+        throw new UnsupportedOperationException("Root registry has no type");
+    }
+
+    @Override
+    public void update(@Nonnull final InstanceIdentifier<? extends DataObject> id,
+                       @Nonnull final List<? extends DataObject> dataBefore,
+                       @Nonnull final List<? extends DataObject> dataAfter,
+                       @Nonnull final WriteContext ctx) {
+        final InstanceIdentifier.PathArgument first = checkNotNull(
+            Iterables.getFirst(id.getPathArguments(), null), "Empty id");
+        final VppWriter<? extends DataObject> vppWriter = rootReaders.get(first.getType());
+        checkNotNull(vppWriter,
+            "Unable to write %s. Missing writer. Current writers for: %s", id, rootReaders.keySet());
+        vppWriter.update(id, dataBefore, dataAfter, ctx);
+    }
+}