HONEYCOMB-130: Separate v3po plugin from HC infra

Creating folders:
- common/
- infra/
- v3po/
- vpp-common/

Change-Id: I2c39e1b17e39e7c0f0628f44aa5fe08563fa06e4
Signed-off-by: Maros Marsalek <mmarsale@cisco.com>

9 files changed, 1078 insertions, 0 deletions

diff --git a/infra/translate-utils/src/test/java/io/fd/honeycomb/v3po/translate/impl/write/util/TransactionWriteContextTest.java b/infra/translate-utils/src/test/java/io/fd/honeycomb/v3po/translate/impl/write/util/TransactionWriteContextTest.java
new file mode 100644
index 000000000..7c93e992a
--- /dev/null
+++ b/infra/translate-utils/src/test/java/io/fd/honeycomb/v3po/translate/impl/write/util/TransactionWriteContextTest.java
@@ -0,0 +1,131 @@
+/*
+ * 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.translate.impl.write.util;
+
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertTrue;
+import static org.mockito.Matchers.any;
+import static org.mockito.Matchers.eq;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+import static org.mockito.MockitoAnnotations.initMocks;
+
+import com.google.common.base.Optional;
+import com.google.common.util.concurrent.Futures;
+import io.fd.honeycomb.v3po.translate.MappingContext;
+import io.fd.honeycomb.v3po.translate.ModificationCache;
+import io.fd.honeycomb.v3po.translate.util.DataObjects;
+import io.fd.honeycomb.v3po.translate.util.write.TransactionWriteContext;
+import java.util.Map;
+import org.junit.Before;
+import org.junit.Test;
+import org.mockito.Mock;
+import org.opendaylight.controller.md.sal.common.api.data.LogicalDatastoreType;
+import org.opendaylight.controller.md.sal.common.api.data.ReadFailedException;
+import org.opendaylight.controller.md.sal.dom.api.DOMDataReadOnlyTransaction;
+import org.opendaylight.yangtools.binding.data.codec.api.BindingNormalizedNodeSerializer;
+import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
+import org.opendaylight.yangtools.yang.common.QName;
+import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
+import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
+
+public class TransactionWriteContextTest {
+
+    @Mock
+    private BindingNormalizedNodeSerializer serializer;
+    @Mock
+    private DOMDataReadOnlyTransaction beforeTx;
+    @Mock
+    private DOMDataReadOnlyTransaction afterTx;
+    @Mock
+    private Map.Entry entry;
+    @Mock
+    private MappingContext contextBroker;
+
+    private TransactionWriteContext transactionWriteContext;
+
+    @Before
+    public void setUp() {
+        initMocks(this);
+        transactionWriteContext = new TransactionWriteContext(serializer, beforeTx, afterTx, contextBroker);
+    }
+
+    @Test
+    public void testReadBeforeNoData() throws Exception {
+        when(beforeTx.read(eq(LogicalDatastoreType.CONFIGURATION), any(YangInstanceIdentifier.class))).thenReturn(
+                Futures.immediateCheckedFuture(Optional.absent()));
+
+        final InstanceIdentifier<DataObjects.DataObject1> instanceId =
+                InstanceIdentifier.create(DataObjects.DataObject1.class);
+
+        final Optional<DataObjects.DataObject1> dataObjects = transactionWriteContext.readBefore(instanceId);
+        assertNotNull(dataObjects);
+        assertFalse(dataObjects.isPresent());
+
+        verify(serializer).toYangInstanceIdentifier(instanceId);
+        verify(serializer, never()).fromNormalizedNode(any(YangInstanceIdentifier.class), any(NormalizedNode.class));
+    }
+
+    @Test
+    public void testReadBefore() throws Exception {
+        when(beforeTx.read(eq(LogicalDatastoreType.CONFIGURATION), any(YangInstanceIdentifier.class))).thenReturn(
+                Futures.immediateCheckedFuture(Optional.of(mock(NormalizedNode.class))));
+
+        final InstanceIdentifier<DataObjects.DataObject1> instanceId =
+                InstanceIdentifier.create(DataObjects.DataObject1.class);
+        final YangInstanceIdentifier yangId = YangInstanceIdentifier.builder().node(QName.create("n", "d")).build();
+        when(serializer.toYangInstanceIdentifier(any(InstanceIdentifier.class))).thenReturn(yangId);
+        when(serializer.fromNormalizedNode(eq(yangId), any(NormalizedNode.class))).thenReturn(entry);
+        when(entry.getValue()).thenReturn(mock(DataObjects.DataObject1.class));
+
+        final Optional<DataObjects.DataObject1> dataObjects = transactionWriteContext.readBefore(instanceId);
+        assertNotNull(dataObjects);
+        assertTrue(dataObjects.isPresent());
+
+        verify(serializer).toYangInstanceIdentifier(instanceId);
+        verify(serializer).fromNormalizedNode(eq(yangId), any(NormalizedNode.class));
+    }
+
+    @Test(expected = IllegalStateException.class)
+    public void testReadBeforeFailed() throws Exception {
+        when(beforeTx.read(eq(LogicalDatastoreType.CONFIGURATION), any(YangInstanceIdentifier.class))).thenReturn(
+                Futures.immediateFailedCheckedFuture(mock(ReadFailedException.class)));
+        transactionWriteContext.readBefore(mock(InstanceIdentifier.class));
+    }
+
+    @Test(expected = IllegalStateException.class)
+    public void testReadAfterFailed() throws Exception {
+        when(afterTx.read(eq(LogicalDatastoreType.CONFIGURATION), any(YangInstanceIdentifier.class))).thenReturn(
+                Futures.immediateFailedCheckedFuture(mock(ReadFailedException.class)));
+        transactionWriteContext.readAfter(mock(InstanceIdentifier.class));
+    }
+
+    @Test
+    public void testGetContext() throws Exception {
+        assertNotNull(transactionWriteContext.getModificationCache());
+    }
+
+    @Test
+    public void testClose() throws Exception {
+        final ModificationCache context = transactionWriteContext.getModificationCache();
+        transactionWriteContext.close();
+        // TODO verify context was closed
+    }
+}
\ No newline at end of file
diff --git a/infra/translate-utils/src/test/java/io/fd/honeycomb/v3po/translate/util/DataObjects.java b/infra/translate-utils/src/test/java/io/fd/honeycomb/v3po/translate/util/DataObjects.java
new file mode 100644
index 000000000..d823465bd
--- /dev/null
+++ b/infra/translate-utils/src/test/java/io/fd/honeycomb/v3po/translate/util/DataObjects.java
@@ -0,0 +1,52 @@
+/*
+ * 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.translate.util;
+
+import org.opendaylight.yangtools.yang.binding.ChildOf;
+import org.opendaylight.yangtools.yang.binding.DataObject;
+import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
+
+public class DataObjects {
+    public interface DataObject1 extends DataObject {
+        InstanceIdentifier<DataObject1> IID = InstanceIdentifier.create(DataObject1.class);
+    }
+
+    public interface DataObject2 extends DataObject {
+        InstanceIdentifier<DataObject2> IID = InstanceIdentifier.create(DataObject2.class);
+    }
+
+    public interface DataObject3 extends DataObject {
+        InstanceIdentifier<DataObject3> IID = InstanceIdentifier.create(DataObject3.class);
+        interface DataObject31 extends DataObject, ChildOf<DataObject3> {
+            InstanceIdentifier<DataObject31> IID = DataObject3.IID.child(DataObject31.class);
+        }
+    }
+
+    public interface DataObject4 extends DataObject {
+        InstanceIdentifier<DataObject4> IID = InstanceIdentifier.create(DataObject4.class);
+        interface DataObject41 extends DataObject, ChildOf<DataObject4> {
+            InstanceIdentifier<DataObject41> IID = DataObject4.IID.child(DataObject41.class);
+            interface DataObject411 extends DataObject, ChildOf<DataObject41> {
+                InstanceIdentifier<DataObject411> IID = DataObject41.IID.child(DataObject411.class);
+            }
+        }
+
+        interface DataObject42 extends DataObject, ChildOf<DataObject4> {
+            InstanceIdentifier<DataObject42> IID = DataObject4.IID.child(DataObject42.class);
+        }
+    }
+}
diff --git a/infra/translate-utils/src/test/java/io/fd/honeycomb/v3po/translate/util/JsonUtilsTest.java b/infra/translate-utils/src/test/java/io/fd/honeycomb/v3po/translate/util/JsonUtilsTest.java
new file mode 100644
index 000000000..bd48cb446
--- /dev/null
+++ b/infra/translate-utils/src/test/java/io/fd/honeycomb/v3po/translate/util/JsonUtilsTest.java
@@ -0,0 +1,109 @@
+/*
+ * 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.translate.util;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
+import com.google.common.io.ByteStreams;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.StandardOpenOption;
+import org.junit.Before;
+import org.junit.Test;
+import org.mockito.MockitoAnnotations;
+import org.opendaylight.yangtools.yang.common.QName;
+import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
+import org.opendaylight.yangtools.yang.data.api.schema.ContainerNode;
+import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
+import org.opendaylight.yangtools.yang.data.impl.schema.Builders;
+import org.opendaylight.yangtools.yang.data.impl.schema.ImmutableNodes;
+import org.opendaylight.yangtools.yang.parser.stmt.reactor.CrossSourceStatementReactor;
+import org.opendaylight.yangtools.yang.parser.stmt.rfc6020.YangInferencePipeline;
+import org.opendaylight.yangtools.yang.parser.stmt.rfc6020.YangStatementSourceImpl;
+import org.opendaylight.yangtools.yang.parser.stmt.rfc6020.effective.EffectiveSchemaContext;
+
+public class JsonUtilsTest {
+
+    public static final String NAMESPACE = "urn:opendaylight:params:xml:ns:yang:test:persistence";
+
+    private static final QName ROOT_QNAME = QName.create("urn:ietf:params:xml:ns:netconf:base:1.0",  "data");
+    private static final QName TOP_CONTAINER_NAME = QName.create(NAMESPACE, "2015-01-05", "top-container");
+    private static final QName TOP_CONTAINER2_NAME = QName.create(NAMESPACE, "2015-01-05", "top-container2");
+    private static final QName STRING_LEAF_QNAME = QName.create(TOP_CONTAINER_NAME, "string");
+
+    private Path tmpPersistFile;
+    private EffectiveSchemaContext effectiveSchemaContext;
+
+    @Before
+    public void setUp() throws Exception {
+        MockitoAnnotations.initMocks(this);
+        tmpPersistFile = Files.createTempFile("testing-hc-persistence", "json");
+
+        final CrossSourceStatementReactor.BuildAction buildAction = YangInferencePipeline.RFC6020_REACTOR.newBuild();
+        buildAction.addSource(new YangStatementSourceImpl(getClass().getResourceAsStream("/test-persistence.yang")));
+        effectiveSchemaContext = buildAction.buildEffective();
+    }
+
+    @Test
+    public void testPersist() throws Exception {
+
+        NormalizedNode<?, ?> data = getData("testing");
+        JsonUtils.writeJsonRoot(data, effectiveSchemaContext, Files.newOutputStream(tmpPersistFile, StandardOpenOption.CREATE));
+        assertTrue(Files.exists(tmpPersistFile));
+
+        String persisted = new String(Files.readAllBytes(tmpPersistFile));
+        String expected =
+            new String(ByteStreams.toByteArray(getClass().getResourceAsStream("/expected-persisted-output.txt")));
+
+        assertEquals(expected, persisted);
+
+        data = getData("testing2");
+        JsonUtils.writeJsonRoot(data, effectiveSchemaContext, Files.newOutputStream(tmpPersistFile, StandardOpenOption.CREATE));
+        persisted = new String(Files.readAllBytes(tmpPersistFile));
+        assertEquals(expected.replace("testing", "testing2"), persisted);
+
+        // File has to stay even after close
+        assertTrue(Files.exists(tmpPersistFile));
+    }
+
+    @Test
+    public void testRestore() throws Exception {
+        final ContainerNode normalizedNodeOptional = JsonUtils
+            .readJsonRoot(effectiveSchemaContext, getClass().getResourceAsStream("/expected-persisted-output.txt"));
+        assertEquals(getData("testing"), normalizedNodeOptional);
+    }
+
+    @Test(expected = IllegalArgumentException.class)
+    public void testRestoreInvalidFile() throws Exception {
+        JsonUtils.readJsonRoot(effectiveSchemaContext, getClass().getResourceAsStream("/test-persistence.yang"));
+    }
+
+    private ContainerNode getData(final String stringValue) {
+        return Builders.containerBuilder()
+            .withNodeIdentifier(new YangInstanceIdentifier.NodeIdentifier(ROOT_QNAME))
+            .withChild(Builders.containerBuilder()
+                .withNodeIdentifier(new YangInstanceIdentifier.NodeIdentifier(TOP_CONTAINER_NAME))
+                .withChild(ImmutableNodes.leafNode(STRING_LEAF_QNAME, stringValue))
+                .build())
+            .withChild(Builders.containerBuilder()
+                .withNodeIdentifier(new YangInstanceIdentifier.NodeIdentifier(TOP_CONTAINER2_NAME))
+                .withChild(ImmutableNodes.leafNode(STRING_LEAF_QNAME, stringValue))
+                .build())
+            .build();
+    }
+}
\ No newline at end of file
diff --git a/infra/translate-utils/src/test/java/io/fd/honeycomb/v3po/translate/util/read/registry/CompositeReaderRegistryBuilderTest.java b/infra/translate-utils/src/test/java/io/fd/honeycomb/v3po/translate/util/read/registry/CompositeReaderRegistryBuilderTest.java
new file mode 100644
index 000000000..e57dcee43
--- /dev/null
+++ b/infra/translate-utils/src/test/java/io/fd/honeycomb/v3po/translate/util/read/registry/CompositeReaderRegistryBuilderTest.java
@@ -0,0 +1,114 @@
+/*
+ * 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.translate.util.read.registry;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+import static org.mockito.Mockito.when;
+
+import com.google.common.collect.ImmutableMap;
+import com.google.common.collect.Lists;
+import io.fd.honeycomb.v3po.translate.read.Reader;
+import io.fd.honeycomb.v3po.translate.read.registry.ReaderRegistry;
+import io.fd.honeycomb.v3po.translate.util.DataObjects;
+import java.util.List;
+import java.util.Map;
+import org.junit.Test;
+import org.mockito.Mockito;
+import org.opendaylight.yangtools.concepts.Builder;
+import org.opendaylight.yangtools.yang.binding.DataObject;
+import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
+
+public class CompositeReaderRegistryBuilderTest {
+
+    private Reader<DataObjects.DataObject1, Builder<DataObjects.DataObject1>> reader1 =
+            mock(DataObjects.DataObject1.class);
+    private Reader<DataObjects.DataObject2, Builder<DataObjects.DataObject2>> reader2 =
+            mock(DataObjects.DataObject2.class);
+    private Reader<DataObjects.DataObject3, Builder<DataObjects.DataObject3>> reader3 =
+            mock(DataObjects.DataObject3.class);
+    private Reader<DataObjects.DataObject3.DataObject31, Builder<DataObjects.DataObject3.DataObject31>> reader31 =
+            mock(DataObjects.DataObject3.DataObject31.class);
+
+    private Reader<DataObjects.DataObject4, Builder<DataObjects.DataObject4>> reader4 =
+            mock(DataObjects.DataObject4.class);
+    private Reader<DataObjects.DataObject4.DataObject41, Builder<DataObjects.DataObject4.DataObject41>> reader41 =
+            mock(DataObjects.DataObject4.DataObject41.class);
+    private Reader<DataObjects.DataObject4.DataObject41.DataObject411, Builder<DataObjects.DataObject4.DataObject41.DataObject411>> reader411 =
+            mock(DataObjects.DataObject4.DataObject41.DataObject411.class);
+    private Reader<DataObjects.DataObject4.DataObject42, Builder<DataObjects.DataObject4.DataObject42>> reader42 =
+            mock(DataObjects.DataObject4.DataObject42.class);
+
+    @SuppressWarnings("unchecked")
+    private <D extends DataObject> Reader<D, Builder<D>> mock(final Class<D> dataObjectType) {
+        final Reader<D, Builder<D>> mock = Mockito.mock(Reader.class);
+        try {
+            when(mock.getManagedDataObjectType())
+                    .thenReturn(((InstanceIdentifier<D>) dataObjectType.getDeclaredField("IID").get(null)));
+        } catch (IllegalAccessException | NoSuchFieldException e) {
+            throw new RuntimeException(e);
+        }
+        return mock;
+    }
+
+    @Test
+    public void testCompositeStructure() throws Exception {
+        final CompositeReaderRegistryBuilder compositeReaderRegistryBuilder = new CompositeReaderRegistryBuilder();
+        /*
+            Composite reader structure ordered left from right
+
+            1,      2,      3,      4
+                            31      42, 41
+                                        411
+         */
+        compositeReaderRegistryBuilder.add(reader1);
+        compositeReaderRegistryBuilder.addAfter(reader2, reader1.getManagedDataObjectType());
+        compositeReaderRegistryBuilder.addAfter(reader3, reader2.getManagedDataObjectType());
+        compositeReaderRegistryBuilder.addAfter(reader31, reader1.getManagedDataObjectType());
+        compositeReaderRegistryBuilder.addAfter(reader4, reader3.getManagedDataObjectType());
+        compositeReaderRegistryBuilder.add(reader41);
+        compositeReaderRegistryBuilder.addBefore(reader42, reader41.getManagedDataObjectType());
+        compositeReaderRegistryBuilder.add(reader411);
+
+        final ReaderRegistry build = compositeReaderRegistryBuilder.build();
+
+        final Map<Class<? extends DataObject>, Reader<? extends DataObject, ? extends Builder<?>>> rootReaders =
+                ((CompositeReaderRegistry) build).getRootReaders();
+        final List<Class<? extends DataObject>> rootReaderOrder = Lists.newArrayList(rootReaders.keySet());
+
+        assertEquals(reader1.getManagedDataObjectType().getTargetType(), rootReaderOrder.get(0));
+        assertEquals(reader2.getManagedDataObjectType().getTargetType(), rootReaderOrder.get(1));
+        assertEquals(reader3.getManagedDataObjectType().getTargetType(), rootReaderOrder.get(2));
+        assertEquals(reader4.getManagedDataObjectType().getTargetType(), rootReaderOrder.get(3));
+
+        assertFalse(rootReaders.get(DataObjects.DataObject1.class) instanceof CompositeReader);
+        assertFalse(rootReaders.get(DataObjects.DataObject2.class) instanceof CompositeReader);
+        assertTrue(rootReaders.get(DataObjects.DataObject3.class) instanceof CompositeReader);
+        assertTrue(rootReaders.get(DataObjects.DataObject4.class) instanceof CompositeReader);
+
+        final ImmutableMap<Class<?>, Reader<? extends DataObject, ? extends Builder<?>>> childReaders =
+                ((CompositeReader<? extends DataObject, ? extends Builder<?>>) rootReaders
+                        .get(DataObjects.DataObject4.class)).getChildReaders();
+        final List<Class<?>> orderedChildReaders = Lists.newArrayList(childReaders.keySet());
+
+        assertEquals(reader42.getManagedDataObjectType().getTargetType(), orderedChildReaders.get(0));
+        assertEquals(reader41.getManagedDataObjectType().getTargetType(), orderedChildReaders.get(1));
+        assertTrue(childReaders.get(DataObjects.DataObject4.DataObject41.class) instanceof CompositeReader);
+        assertFalse(childReaders.get(DataObjects.DataObject4.DataObject42.class) instanceof CompositeReader);
+    }
+}
\ No newline at end of file
diff --git a/infra/translate-utils/src/test/java/io/fd/honeycomb/v3po/translate/util/read/registry/SubtreeReaderTest.java b/infra/translate-utils/src/test/java/io/fd/honeycomb/v3po/translate/util/read/registry/SubtreeReaderTest.java
new file mode 100644
index 000000000..324d71daa
--- /dev/null
+++ b/infra/translate-utils/src/test/java/io/fd/honeycomb/v3po/translate/util/read/registry/SubtreeReaderTest.java
@@ -0,0 +1,124 @@
+/*
+ * 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.translate.util.read.registry;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.mockito.Mockito.atLeastOnce;
+import static org.mockito.Mockito.doReturn;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.verify;
+
+import com.google.common.base.Optional;
+import com.google.common.collect.Sets;
+import io.fd.honeycomb.v3po.translate.read.ReadContext;
+import io.fd.honeycomb.v3po.translate.read.Reader;
+import io.fd.honeycomb.v3po.translate.util.DataObjects;
+import org.junit.Before;
+import org.junit.Test;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+import org.opendaylight.yangtools.concepts.Builder;
+import org.opendaylight.yangtools.yang.binding.ChildOf;
+import org.opendaylight.yangtools.yang.binding.DataObject;
+import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
+
+public class SubtreeReaderTest {
+
+    @Mock
+    private Reader<DataObjects.DataObject4, Builder<DataObjects.DataObject4>> delegate;
+    @Mock
+    private Reader<DataObject1, Builder<DataObject1>> delegateLocal;
+    @Mock
+    private ReadContext ctx;
+
+    @Before
+    public void setUp() throws Exception {
+        MockitoAnnotations.initMocks(this);
+        doReturn(DataObjects.DataObject4.IID).when(delegate).getManagedDataObjectType();
+        doReturn(DataObject1.IID).when(delegateLocal).getManagedDataObjectType();
+    }
+
+    @Test
+    public void testCreate() throws Exception {
+        final Reader<DataObjects.DataObject4, Builder<DataObjects.DataObject4>> subtreeR =
+                SubtreeReader.createForReader(Sets.newHashSet(DataObjects.DataObject4.DataObject41.IID), delegate);
+
+        subtreeR.getBuilder(DataObjects.DataObject4.IID);
+        verify(delegate).getBuilder(DataObjects.DataObject4.IID);
+
+        subtreeR.getManagedDataObjectType();
+        verify(delegate, atLeastOnce()).getManagedDataObjectType();
+    }
+
+    @Test(expected = IllegalArgumentException.class)
+    public void testCreateInvalid() throws Exception {
+        SubtreeReader.createForReader(Sets.newHashSet(DataObjects.DataObject1.IID), delegate);
+    }
+
+    @Test(expected = IllegalStateException.class)
+    public void testReadOnlySubtreeCannotFilter() throws Exception {
+        final Reader<DataObjects.DataObject4, Builder<DataObjects.DataObject4>> subtreeR =
+                SubtreeReader.createForReader(Sets.newHashSet(DataObjects.DataObject4.DataObject41.IID), delegate);
+
+        doReturn(Optional.fromNullable(mock(DataObjects.DataObject4.class))).when(delegate).read(DataObjects.DataObject4.IID, ctx);
+        subtreeR.read(DataObjects.DataObject4.DataObject41.IID, ctx);
+    }
+
+    @Test
+    public void testReadOnlySubtreeNotPresent() throws Exception {
+        final Reader<DataObjects.DataObject4, Builder<DataObjects.DataObject4>> subtreeR =
+                SubtreeReader.createForReader(Sets.newHashSet(DataObjects.DataObject4.DataObject41.IID), delegate);
+
+        doReturn(Optional.absent()).when(delegate).read(DataObjects.DataObject4.IID, ctx);
+        assertFalse(subtreeR.read(DataObjects.DataObject4.DataObject41.IID, ctx).isPresent());
+    }
+
+    @Test
+    public void testReadOnlySubtreeChild() throws Exception {
+        final Reader<DataObject1, Builder<DataObject1>> subtreeR =
+                SubtreeReader.createForReader(Sets.newHashSet(DataObject1.DataObject11.IID), delegateLocal);
+
+        final DataObject1 mock = mock(DataObject1.class);
+        final DataObject1.DataObject11 mock11 = mock(DataObject1.DataObject11.class);
+        doReturn(mock11).when(mock).getDataObject11();
+        doReturn(Optional.fromNullable(mock)).when(delegateLocal).read(DataObject1.IID, ctx);
+        assertEquals(mock11, subtreeR.read(DataObject1.DataObject11.IID, ctx).get());
+    }
+
+    @Test
+    public void testReadEntireSubtree() throws Exception {
+        final Reader<DataObject1, Builder<DataObject1>> subtreeR =
+                SubtreeReader.createForReader(Sets.newHashSet(DataObject1.DataObject11.IID), delegateLocal);
+
+        final DataObject1 mock = mock(DataObject1.class);
+        final DataObject1.DataObject11 mock11 = mock(DataObject1.DataObject11.class);
+        doReturn(mock11).when(mock).getDataObject11();
+        doReturn(Optional.fromNullable(mock)).when(delegateLocal).read(DataObject1.IID, ctx);
+        assertEquals(mock, subtreeR.read(DataObject1.IID, ctx).get());
+    }
+
+    public abstract static class DataObject1 implements DataObject {
+        public static InstanceIdentifier<DataObject1> IID = InstanceIdentifier.create(DataObject1.class);
+
+        public abstract DataObject11 getDataObject11();
+
+        public abstract static class DataObject11 implements DataObject, ChildOf<DataObject1> {
+            public static InstanceIdentifier<DataObject11> IID = DataObject1.IID.child(DataObject11.class);
+        }
+    }
+}
diff --git a/infra/translate-utils/src/test/java/io/fd/honeycomb/v3po/translate/util/read/registry/TypeHierarchyTest.java b/infra/translate-utils/src/test/java/io/fd/honeycomb/v3po/translate/util/read/registry/TypeHierarchyTest.java
new file mode 100644
index 000000000..7a664eef1
--- /dev/null
+++ b/infra/translate-utils/src/test/java/io/fd/honeycomb/v3po/translate/util/read/registry/TypeHierarchyTest.java
@@ -0,0 +1,69 @@
+/*
+ * 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.translate.util.read.registry;
+
+import static org.hamcrest.CoreMatchers.hasItem;
+import static org.hamcrest.CoreMatchers.hasItems;
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertThat;
+import static org.junit.Assert.assertTrue;
+
+import com.google.common.collect.Sets;
+import io.fd.honeycomb.v3po.translate.util.DataObjects.DataObject1;
+import io.fd.honeycomb.v3po.translate.util.DataObjects.DataObject3;
+import io.fd.honeycomb.v3po.translate.util.DataObjects.DataObject4;
+import org.junit.Test;
+
+public class TypeHierarchyTest {
+
+    @Test
+    public void testHierarchy() throws Exception {
+        final TypeHierarchy typeHierarchy = TypeHierarchy.create(Sets.newHashSet(
+                DataObject4.DataObject41.DataObject411.IID,
+                DataObject4.DataObject41.IID,/* Included in previous already */
+                DataObject1.IID,
+                DataObject3.DataObject31.IID));
+
+        // Roots
+        assertThat(typeHierarchy.getRoots().size(), is(3));
+        assertThat(typeHierarchy.getRoots(), hasItems(DataObject1.IID, DataObject3.IID, DataObject4.IID));
+
+        // Leaves
+        assertThat(typeHierarchy.getDirectChildren(DataObject1.IID).size(), is(0));
+        assertThat(typeHierarchy.getDirectChildren(DataObject3.DataObject31.IID).size(), is(0));
+        assertThat(typeHierarchy.getDirectChildren(DataObject4.DataObject41.DataObject411.IID).size(), is(0));
+
+        // Intermediate leaves
+        assertThat(typeHierarchy.getDirectChildren(DataObject3.IID).size(), is(1));
+        assertThat(typeHierarchy.getDirectChildren(DataObject3.IID), hasItem(DataObject3.DataObject31.IID));
+        assertEquals(typeHierarchy.getDirectChildren(DataObject3.IID), typeHierarchy.getAllChildren(DataObject3.IID));
+
+        assertThat(typeHierarchy.getDirectChildren(DataObject4.DataObject41.IID).size(), is(1));
+        assertThat(typeHierarchy.getDirectChildren(DataObject4.DataObject41.IID), hasItem(
+                DataObject4.DataObject41.DataObject411.IID));
+        assertEquals(typeHierarchy.getDirectChildren(DataObject4.DataObject41.IID), typeHierarchy.getAllChildren(
+                DataObject4.DataObject41.IID));
+
+        assertThat(typeHierarchy.getDirectChildren(DataObject4.IID).size(), is(1));
+        assertThat(typeHierarchy.getDirectChildren(DataObject4.IID), hasItem(DataObject4.DataObject41.IID));
+        assertThat(typeHierarchy.getAllChildren(DataObject4.IID).size(), is(2));
+        assertTrue(typeHierarchy.getAllChildren(DataObject4.IID).contains(DataObject4.DataObject41.IID));
+        assertTrue(typeHierarchy.getAllChildren(DataObject4.IID).contains(DataObject4.DataObject41.DataObject411.IID));
+    }
+}
+
diff --git a/infra/translate-utils/src/test/java/io/fd/honeycomb/v3po/translate/util/write/registry/FlatWriterRegistryBuilderTest.java b/infra/translate-utils/src/test/java/io/fd/honeycomb/v3po/translate/util/write/registry/FlatWriterRegistryBuilderTest.java
new file mode 100644
index 000000000..743d84cbf
--- /dev/null
+++ b/infra/translate-utils/src/test/java/io/fd/honeycomb/v3po/translate/util/write/registry/FlatWriterRegistryBuilderTest.java
@@ -0,0 +1,131 @@
+package io.fd.honeycomb.v3po.translate.util.write.registry;
+
+import static org.hamcrest.CoreMatchers.anyOf;
+import static org.hamcrest.CoreMatchers.equalTo;
+import static org.hamcrest.CoreMatchers.hasItems;
+import static org.hamcrest.CoreMatchers.instanceOf;
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertThat;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+
+import com.google.common.collect.ImmutableMap;
+import com.google.common.collect.Lists;
+import com.google.common.collect.Sets;
+import io.fd.honeycomb.v3po.translate.util.DataObjects;
+import io.fd.honeycomb.v3po.translate.write.Writer;
+import java.util.ArrayList;
+import java.util.List;
+import org.junit.Test;
+import org.opendaylight.yangtools.yang.binding.DataObject;
+import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
+
+public class FlatWriterRegistryBuilderTest {
+
+
+    @Test
+    public void testRelationsBefore() throws Exception {
+        final FlatWriterRegistryBuilder flatWriterRegistryBuilder = new FlatWriterRegistryBuilder();
+        /*
+            1   ->  2   ->  3
+                        ->  4
+         */
+        flatWriterRegistryBuilder.add(mockWriter(DataObjects.DataObject3.class));
+        flatWriterRegistryBuilder.add(mockWriter(DataObjects.DataObject4.class));
+        flatWriterRegistryBuilder.addBefore(mockWriter(DataObjects.DataObject2.class),
+                Lists.newArrayList(DataObjects.DataObject3.IID, DataObjects.DataObject4.IID));
+        flatWriterRegistryBuilder.addBefore(mockWriter(DataObjects.DataObject1.class), DataObjects.DataObject2.IID);
+        final ImmutableMap<InstanceIdentifier<?>, Writer<?>> mappedWriters =
+                flatWriterRegistryBuilder.getMappedHandlers();
+
+        final ArrayList<InstanceIdentifier<?>> typesInList = Lists.newArrayList(mappedWriters.keySet());
+        assertEquals(DataObjects.DataObject1.IID, typesInList.get(0));
+        assertEquals(DataObjects.DataObject2.IID, typesInList.get(1));
+        assertThat(typesInList.get(2), anyOf(equalTo(DataObjects.DataObject3.IID), equalTo(DataObjects.DataObject4.IID)));
+        assertThat(typesInList.get(3), anyOf(equalTo(DataObjects.DataObject3.IID), equalTo(DataObjects.DataObject4.IID)));
+    }
+
+    @Test
+    public void testRelationsAfter() throws Exception {
+        final FlatWriterRegistryBuilder flatWriterRegistryBuilder = new FlatWriterRegistryBuilder();
+        /*
+            1   ->  2   ->  3
+                        ->  4
+         */
+        flatWriterRegistryBuilder.add(mockWriter(DataObjects.DataObject1.class));
+        flatWriterRegistryBuilder.addAfter(mockWriter(DataObjects.DataObject2.class), DataObjects.DataObject1.IID);
+        flatWriterRegistryBuilder.addAfter(mockWriter(DataObjects.DataObject3.class), DataObjects.DataObject2.IID);
+        flatWriterRegistryBuilder.addAfter(mockWriter(DataObjects.DataObject4.class), DataObjects.DataObject2.IID);
+        final ImmutableMap<InstanceIdentifier<?>, Writer<?>> mappedWriters =
+                flatWriterRegistryBuilder.getMappedHandlers();
+
+        final List<InstanceIdentifier<?>> typesInList = Lists.newArrayList(mappedWriters.keySet());
+        assertEquals(DataObjects.DataObject1.IID, typesInList.get(0));
+        assertEquals(DataObjects.DataObject2.IID, typesInList.get(1));
+        assertThat(typesInList.get(2), anyOf(equalTo(DataObjects.DataObject3.IID), equalTo(DataObjects.DataObject4.IID)));
+        assertThat(typesInList.get(3), anyOf(equalTo(DataObjects.DataObject3.IID), equalTo(DataObjects.DataObject4.IID)));
+    }
+
+    @Test(expected = IllegalArgumentException.class)
+    public void testRelationsLoop() throws Exception {
+        final FlatWriterRegistryBuilder flatWriterRegistryBuilder = new FlatWriterRegistryBuilder();
+        /*
+            1   ->  2   ->  1
+         */
+        flatWriterRegistryBuilder.add(mockWriter(DataObjects.DataObject1.class));
+        flatWriterRegistryBuilder.addAfter(mockWriter(DataObjects.DataObject2.class), DataObjects.DataObject1.IID);
+        flatWriterRegistryBuilder.addAfter(mockWriter(DataObjects.DataObject1.class), DataObjects.DataObject2.IID);
+    }
+
+    @Test(expected = IllegalArgumentException.class)
+    public void testAddWriterTwice() throws Exception {
+        final FlatWriterRegistryBuilder flatWriterRegistryBuilder = new FlatWriterRegistryBuilder();
+        flatWriterRegistryBuilder.add(mockWriter(DataObjects.DataObject1.class));
+        flatWriterRegistryBuilder.add(mockWriter(DataObjects.DataObject1.class));
+    }
+
+    @Test
+    public void testAddSubtreeWriter() throws Exception {
+        final FlatWriterRegistryBuilder flatWriterRegistryBuilder = new FlatWriterRegistryBuilder();
+        flatWriterRegistryBuilder.subtreeAdd(
+                Sets.newHashSet(DataObjects.DataObject4.DataObject41.IID,
+                                DataObjects.DataObject4.DataObject41.IID),
+                mockWriter(DataObjects.DataObject4.class));
+        final ImmutableMap<InstanceIdentifier<?>, Writer<?>> mappedWriters =
+                flatWriterRegistryBuilder.getMappedHandlers();
+        final ArrayList<InstanceIdentifier<?>> typesInList = Lists.newArrayList(mappedWriters.keySet());
+
+        assertEquals(DataObjects.DataObject4.IID, typesInList.get(0));
+        assertEquals(1, typesInList.size());
+    }
+
+    @Test
+    public void testCreateSubtreeWriter() throws Exception {
+        final Writer<?> forWriter = SubtreeWriter.createForWriter(Sets.newHashSet(
+                DataObjects.DataObject4.DataObject41.IID,
+                DataObjects.DataObject4.DataObject41.DataObject411.IID,
+                DataObjects.DataObject4.DataObject42.IID),
+                mockWriter(DataObjects.DataObject4.class));
+        assertThat(forWriter, instanceOf(SubtreeWriter.class));
+        assertThat(((SubtreeWriter<?>) forWriter).getHandledChildTypes().size(), is(3));
+        assertThat(((SubtreeWriter<?>) forWriter).getHandledChildTypes(), hasItems(DataObjects.DataObject4.DataObject41.IID,
+                DataObjects.DataObject4.DataObject42.IID, DataObjects.DataObject4.DataObject41.DataObject411.IID));
+    }
+
+    @Test(expected = IllegalArgumentException.class)
+    public void testCreateInvalidSubtreeWriter() throws Exception {
+        SubtreeWriter.createForWriter(Sets.newHashSet(
+                InstanceIdentifier.create(DataObjects.DataObject3.class).child(DataObjects.DataObject3.DataObject31.class)),
+                mockWriter(DataObjects.DataObject4.class));
+    }
+
+    @SuppressWarnings("unchecked")
+    private Writer<? extends DataObject> mockWriter(final Class<? extends DataObject> doClass)
+            throws NoSuchFieldException, IllegalAccessException {
+        final Writer mock = mock(Writer.class);
+        when(mock.getManagedDataObjectType()).thenReturn((InstanceIdentifier<?>) doClass.getDeclaredField("IID").get(null));
+        return mock;
+    }
+
+}
\ No newline at end of file
diff --git a/infra/translate-utils/src/test/java/io/fd/honeycomb/v3po/translate/util/write/registry/FlatWriterRegistryTest.java b/infra/translate-utils/src/test/java/io/fd/honeycomb/v3po/translate/util/write/registry/FlatWriterRegistryTest.java
new file mode 100644
index 000000000..a72cb4fa7
--- /dev/null
+++ b/infra/translate-utils/src/test/java/io/fd/honeycomb/v3po/translate/util/write/registry/FlatWriterRegistryTest.java
@@ -0,0 +1,264 @@
+package io.fd.honeycomb.v3po.translate.util.write.registry;
+
+import static org.hamcrest.CoreMatchers.hasItem;
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertThat;
+import static org.junit.Assert.fail;
+import static org.mockito.Matchers.any;
+import static org.mockito.Mockito.doThrow;
+import static org.mockito.Mockito.inOrder;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.verifyNoMoreInteractions;
+import static org.mockito.Mockito.verifyZeroInteractions;
+import static org.mockito.Mockito.when;
+
+import com.google.common.collect.HashMultimap;
+import com.google.common.collect.ImmutableMap;
+import com.google.common.collect.ImmutableMultimap;
+import com.google.common.collect.Multimap;
+import io.fd.honeycomb.v3po.translate.util.DataObjects.DataObject1;
+import io.fd.honeycomb.v3po.translate.util.DataObjects.DataObject2;
+import io.fd.honeycomb.v3po.translate.util.DataObjects.DataObject3;
+import io.fd.honeycomb.v3po.translate.write.DataObjectUpdate;
+import io.fd.honeycomb.v3po.translate.write.WriteContext;
+import io.fd.honeycomb.v3po.translate.write.Writer;
+import io.fd.honeycomb.v3po.translate.write.registry.WriterRegistry;
+import org.junit.Before;
+import org.junit.Test;
+import org.mockito.InOrder;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+import org.opendaylight.yangtools.yang.binding.DataObject;
+import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
+
+public class FlatWriterRegistryTest {
+
+    @Mock
+    private Writer<DataObject1> writer1;
+    @Mock
+    private Writer<DataObject2> writer2;
+    @Mock
+    private Writer<DataObject3> writer3;
+    @Mock
+    private WriteContext ctx;
+
+    @Before
+    public void setUp() throws Exception {
+        MockitoAnnotations.initMocks(this);
+        when(writer1.getManagedDataObjectType()).thenReturn(DataObject1.IID);
+        when(writer2.getManagedDataObjectType()).thenReturn(DataObject2.IID);
+        when(writer3.getManagedDataObjectType()).thenReturn(DataObject3.IID);
+    }
+
+    @Test
+    public void testMultipleUpdatesForSingleWriter() throws Exception {
+        final FlatWriterRegistry flatWriterRegistry =
+                new FlatWriterRegistry(ImmutableMap.of(DataObject1.IID, writer1, DataObject2.IID, writer2));
+
+        final Multimap<InstanceIdentifier<?>, DataObjectUpdate> updates = HashMultimap.create();
+        final InstanceIdentifier<DataObject1> iid = InstanceIdentifier.create(DataObject1.class);
+        final InstanceIdentifier<DataObject1> iid2 = InstanceIdentifier.create(DataObject1.class);
+        final DataObject1 dataObject = mock(DataObject1.class);
+        updates.put(DataObject1.IID, DataObjectUpdate.create(iid, dataObject, dataObject));
+        updates.put(DataObject1.IID, DataObjectUpdate.create(iid2, dataObject, dataObject));
+        flatWriterRegistry.update(new WriterRegistry.DataObjectUpdates(updates, ImmutableMultimap.of()), ctx);
+
+        verify(writer1).update(iid, dataObject, dataObject, ctx);
+        verify(writer1).update(iid2, dataObject, dataObject, ctx);
+        // Invoked when registry is being created
+        verifyNoMoreInteractions(writer1);
+        verifyZeroInteractions(writer2);
+    }
+
+    @Test
+    public void testMultipleUpdatesForMultipleWriters() throws Exception {
+        final FlatWriterRegistry flatWriterRegistry =
+                new FlatWriterRegistry(ImmutableMap.of(DataObject1.IID, writer1, DataObject2.IID, writer2));
+
+        final Multimap<InstanceIdentifier<?>, DataObjectUpdate> updates = HashMultimap.create();
+        final InstanceIdentifier<DataObject1> iid = InstanceIdentifier.create(DataObject1.class);
+        final DataObject1 dataObject = mock(DataObject1.class);
+        updates.put(DataObject1.IID, DataObjectUpdate.create(iid, dataObject, dataObject));
+        final InstanceIdentifier<DataObject2> iid2 = InstanceIdentifier.create(DataObject2.class);
+        final DataObject2 dataObject2 = mock(DataObject2.class);
+        updates.put(DataObject2.IID, DataObjectUpdate.create(iid2, dataObject2, dataObject2));
+        flatWriterRegistry.update(new WriterRegistry.DataObjectUpdates(updates, ImmutableMultimap.of()), ctx);
+
+        final InOrder inOrder = inOrder(writer1, writer2);
+        inOrder.verify(writer1).update(iid, dataObject, dataObject, ctx);
+        inOrder.verify(writer2).update(iid2, dataObject2, dataObject2, ctx);
+
+        verifyNoMoreInteractions(writer1);
+        verifyNoMoreInteractions(writer2);
+    }
+
+    @Test
+    public void testMultipleDeletesForMultipleWriters() throws Exception {
+        final FlatWriterRegistry flatWriterRegistry =
+                new FlatWriterRegistry(ImmutableMap.of(DataObject1.IID, writer1, DataObject2.IID, writer2));
+
+        final Multimap<InstanceIdentifier<?>, DataObjectUpdate.DataObjectDelete> deletes = HashMultimap.create();
+        final InstanceIdentifier<DataObject1> iid = InstanceIdentifier.create(DataObject1.class);
+        final DataObject1 dataObject = mock(DataObject1.class);
+        deletes.put(DataObject1.IID, ((DataObjectUpdate.DataObjectDelete) DataObjectUpdate.create(iid, dataObject, null)));
+        final InstanceIdentifier<DataObject2> iid2 = InstanceIdentifier.create(DataObject2.class);
+        final DataObject2 dataObject2 = mock(DataObject2.class);
+        deletes.put(DataObject2.IID, ((DataObjectUpdate.DataObjectDelete) DataObjectUpdate.create(iid2, dataObject2, null)));
+        flatWriterRegistry.update(new WriterRegistry.DataObjectUpdates(ImmutableMultimap.of(), deletes), ctx);
+
+        final InOrder inOrder = inOrder(writer1, writer2);
+        // Reversed order of invocation, first writer2 and then writer1
+        inOrder.verify(writer2).update(iid2, dataObject2, null, ctx);
+        inOrder.verify(writer1).update(iid, dataObject, null, ctx);
+
+        verifyNoMoreInteractions(writer1);
+        verifyNoMoreInteractions(writer2);
+    }
+
+    @Test
+    public void testMultipleUpdatesAndDeletesForMultipleWriters() throws Exception {
+        final FlatWriterRegistry flatWriterRegistry =
+                new FlatWriterRegistry(ImmutableMap.of(DataObject1.IID, writer1, DataObject2.IID, writer2));
+
+        final Multimap<InstanceIdentifier<?>, DataObjectUpdate.DataObjectDelete> deletes = HashMultimap.create();
+        final Multimap<InstanceIdentifier<?>, DataObjectUpdate> updates = HashMultimap.create();
+        final InstanceIdentifier<DataObject1> iid = InstanceIdentifier.create(DataObject1.class);
+        final DataObject1 dataObject = mock(DataObject1.class);
+        // Writer 1 delete
+        deletes.put(DataObject1.IID, ((DataObjectUpdate.DataObjectDelete) DataObjectUpdate.create(iid, dataObject, null)));
+        // Writer 1 update
+        updates.put(DataObject1.IID, DataObjectUpdate.create(iid, dataObject, dataObject));
+        final InstanceIdentifier<DataObject2> iid2 = InstanceIdentifier.create(DataObject2.class);
+        final DataObject2 dataObject2 = mock(DataObject2.class);
+        // Writer 2 delete
+        deletes.put(DataObject2.IID, ((DataObjectUpdate.DataObjectDelete) DataObjectUpdate.create(iid2, dataObject2, null)));
+        // Writer 2 update
+        updates.put(DataObject2.IID, DataObjectUpdate.create(iid2, dataObject2, dataObject2));
+        flatWriterRegistry.update(new WriterRegistry.DataObjectUpdates(updates, deletes), ctx);
+
+        final InOrder inOrder = inOrder(writer1, writer2);
+        // Reversed order of invocation, first writer2 and then writer1 for deletes
+        inOrder.verify(writer2).update(iid2, dataObject2, null, ctx);
+        inOrder.verify(writer1).update(iid, dataObject, null, ctx);
+        // Then also updates are processed
+        inOrder.verify(writer1).update(iid, dataObject, dataObject, ctx);
+        inOrder.verify(writer2).update(iid2, dataObject2, dataObject2, ctx);
+
+        verifyNoMoreInteractions(writer1);
+        verifyNoMoreInteractions(writer2);
+    }
+
+    @Test(expected = IllegalArgumentException.class)
+    public void testMultipleUpdatesOneMissing() throws Exception {
+        final FlatWriterRegistry flatWriterRegistry =
+                new FlatWriterRegistry(ImmutableMap.of(DataObject1.IID, writer1));
+
+        final Multimap<InstanceIdentifier<?>, DataObjectUpdate> updates = HashMultimap.create();
+        addUpdate(updates, DataObject1.class);
+        addUpdate(updates, DataObject2.class);
+        flatWriterRegistry.update(new WriterRegistry.DataObjectUpdates(updates, ImmutableMultimap.of()), ctx);
+    }
+
+    @Test
+    public void testMultipleUpdatesOneFailing() throws Exception {
+        final FlatWriterRegistry flatWriterRegistry =
+                new FlatWriterRegistry(ImmutableMap.of(DataObject1.IID, writer1, DataObject2.IID, writer2));
+
+        // Writer1 always fails
+        doThrow(new RuntimeException()).when(writer1)
+                .update(any(InstanceIdentifier.class), any(DataObject.class), any(DataObject.class), any(WriteContext.class));
+
+        final Multimap<InstanceIdentifier<?>, DataObjectUpdate> updates = HashMultimap.create();
+        addUpdate(updates, DataObject1.class);
+        addUpdate(updates, DataObject2.class);
+
+        try {
+            flatWriterRegistry.update(new WriterRegistry.DataObjectUpdates(updates, ImmutableMultimap.of()), ctx);
+            fail("Bulk update should have failed on writer1");
+        } catch (WriterRegistry.BulkUpdateException e) {
+            assertThat(e.getFailedIds().size(), is(2));
+            assertThat(e.getFailedIds(), hasItem(InstanceIdentifier.create(DataObject2.class)));
+            assertThat(e.getFailedIds(), hasItem(InstanceIdentifier.create(DataObject1.class)));
+        }
+    }
+
+    @Test
+    public void testMultipleUpdatesOneFailingThenRevertWithSuccess() throws Exception {
+        final FlatWriterRegistry flatWriterRegistry =
+                new FlatWriterRegistry(
+                        ImmutableMap.of(DataObject1.IID, writer1, DataObject2.IID, writer2, DataObject3.IID, writer3));
+
+        // Writer1 always fails
+        doThrow(new RuntimeException()).when(writer3)
+                .update(any(InstanceIdentifier.class), any(DataObject.class), any(DataObject.class), any(WriteContext.class));
+
+        final Multimap<InstanceIdentifier<?>, DataObjectUpdate> updates = HashMultimap.create();
+        addUpdate(updates, DataObject1.class);
+        addUpdate(updates, DataObject3.class);
+        final InstanceIdentifier<DataObject2> iid2 = InstanceIdentifier.create(DataObject2.class);
+        final DataObject2 before2 = mock(DataObject2.class);
+        final DataObject2 after2 = mock(DataObject2.class);
+        updates.put(DataObject2.IID, DataObjectUpdate.create(iid2, before2, after2));
+
+        try {
+            flatWriterRegistry.update(new WriterRegistry.DataObjectUpdates(updates, ImmutableMultimap.of()), ctx);
+            fail("Bulk update should have failed on writer1");
+        } catch (WriterRegistry.BulkUpdateException e) {
+            assertThat(e.getFailedIds().size(), is(1));
+
+            final InOrder inOrder = inOrder(writer1, writer2, writer3);
+            inOrder.verify(writer1)
+                .update(any(InstanceIdentifier.class), any(DataObject.class), any(DataObject.class), any(WriteContext.class));
+            inOrder.verify(writer2)
+                .update(iid2, before2, after2, ctx);
+            inOrder.verify(writer3)
+                .update(any(InstanceIdentifier.class), any(DataObject.class), any(DataObject.class), any(WriteContext.class));
+
+            e.revertChanges();
+            // Revert changes. Successful updates are iterated in reverse
+            inOrder.verify(writer2)
+                    .update(iid2, after2, before2, ctx);
+            inOrder.verify(writer1)
+                    .update(any(InstanceIdentifier.class), any(DataObject.class), any(DataObject.class), any(WriteContext.class));
+            verifyNoMoreInteractions(writer3);
+        }
+    }
+
+    @Test
+    public void testMultipleUpdatesOneFailingThenRevertWithFail() throws Exception {
+        final FlatWriterRegistry flatWriterRegistry =
+                new FlatWriterRegistry(
+                        ImmutableMap.of(DataObject1.IID, writer1, DataObject2.IID, writer2, DataObject3.IID, writer3));
+
+        // Writer1 always fails
+        doThrow(new RuntimeException()).when(writer3)
+                .update(any(InstanceIdentifier.class), any(DataObject.class), any(DataObject.class), any(WriteContext.class));
+
+        final Multimap<InstanceIdentifier<?>, DataObjectUpdate> updates = HashMultimap.create();
+        addUpdate(updates, DataObject1.class);
+        addUpdate(updates, DataObject2.class);
+        addUpdate(updates, DataObject3.class);
+
+        try {
+            flatWriterRegistry.update(new WriterRegistry.DataObjectUpdates(updates, ImmutableMultimap.of()), ctx);
+            fail("Bulk update should have failed on writer1");
+        } catch (WriterRegistry.BulkUpdateException e) {
+            // Writer1 always fails from now
+            doThrow(new RuntimeException()).when(writer1)
+                    .update(any(InstanceIdentifier.class), any(DataObject.class), any(DataObject.class), any(WriteContext.class));
+            try {
+                e.revertChanges();
+            } catch (WriterRegistry.Reverter.RevertFailedException e1) {
+                assertThat(e1.getNotRevertedChanges().size(), is(1));
+                assertThat(e1.getNotRevertedChanges(), hasItem(InstanceIdentifier.create(DataObject1.class)));
+            }
+        }
+    }
+
+    private <D extends DataObject> void addUpdate(final Multimap<InstanceIdentifier<?>, DataObjectUpdate> updates,
+                           final Class<D> type) throws Exception {
+        final InstanceIdentifier<D> iid = (InstanceIdentifier<D>) type.getDeclaredField("IID").get(null);
+        updates.put(iid, DataObjectUpdate.create(iid, mock(type), mock(type)));
+    }
+}
\ No newline at end of file
diff --git a/infra/translate-utils/src/test/java/io/fd/honeycomb/v3po/translate/util/write/registry/SubtreeWriterTest.java b/infra/translate-utils/src/test/java/io/fd/honeycomb/v3po/translate/util/write/registry/SubtreeWriterTest.java
new file mode 100644
index 000000000..627c69c92
--- /dev/null
+++ b/infra/translate-utils/src/test/java/io/fd/honeycomb/v3po/translate/util/write/registry/SubtreeWriterTest.java
@@ -0,0 +1,84 @@
+/*
+ * 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.translate.util.write.registry;
+
+import static org.hamcrest.CoreMatchers.hasItem;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertThat;
+import static org.mockito.Mockito.when;
+
+import com.google.common.collect.Sets;
+import io.fd.honeycomb.v3po.translate.util.DataObjects;
+import io.fd.honeycomb.v3po.translate.write.Writer;
+import java.util.Collections;
+import org.junit.Before;
+import org.junit.Test;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+import org.opendaylight.yangtools.yang.binding.DataObject;
+import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
+
+public class SubtreeWriterTest {
+
+    @Mock
+    Writer<DataObjects.DataObject4> writer;
+    @Mock
+    Writer<DataObjects.DataObject4.DataObject41> writer11;
+
+    @Before
+    public void setUp() throws Exception {
+        MockitoAnnotations.initMocks(this);
+        when(writer.getManagedDataObjectType()).thenReturn(DataObjects.DataObject4.IID);
+        when(writer11.getManagedDataObjectType()).thenReturn(DataObjects.DataObject4.DataObject41.IID);
+    }
+
+    @Test(expected = IllegalArgumentException.class)
+    public void testSubtreeWriterCreationFail() throws Exception {
+        // The subtree node identified by IID.c(DataObject.class) is not a child of writer.getManagedDataObjectType
+        SubtreeWriter.createForWriter(Collections.singleton(InstanceIdentifier.create(DataObject.class)), writer);
+    }
+
+    @Test(expected = IllegalArgumentException.class)
+    public void testSubtreeWriterCreationFailInvalidIid() throws Exception {
+        // The subtree node identified by IID.c(DataObject.class) is not a child of writer.getManagedDataObjectType
+        SubtreeWriter.createForWriter(Collections.singleton(DataObjects.DataObject4.IID), writer);
+    }
+
+    @Test
+    public void testSubtreeWriterCreation() throws Exception {
+        final SubtreeWriter<?> forWriter = (SubtreeWriter<?>) SubtreeWriter.createForWriter(Sets.newHashSet(
+                DataObjects.DataObject4.DataObject41.IID,
+                DataObjects.DataObject4.DataObject41.DataObject411.IID,
+                DataObjects.DataObject4.DataObject42.IID),
+                writer);
+
+        assertEquals(writer.getManagedDataObjectType(), forWriter.getManagedDataObjectType());
+        assertEquals(3, forWriter.getHandledChildTypes().size());
+    }
+
+    @Test
+    public void testSubtreeWriterHandledTypes() throws Exception {
+        final SubtreeWriter<?> forWriter = (SubtreeWriter<?>) SubtreeWriter.createForWriter(Sets.newHashSet(
+                DataObjects.DataObject4.DataObject41.DataObject411.IID),
+                writer);
+
+        assertEquals(writer.getManagedDataObjectType(), forWriter.getManagedDataObjectType());
+        assertEquals(1, forWriter.getHandledChildTypes().size());
+        assertThat(forWriter.getHandledChildTypes(), hasItem(DataObjects.DataObject4.DataObject41.DataObject411.IID));
+    }
+
+}
\ No newline at end of file