2 * Copyright (c) 2014 Cisco Systems, Inc. and others. All rights reserved.
4 * This program and the accompanying materials are made available under the
5 * terms of the Eclipse Public License v1.0 which accompanies this distribution,
6 * and is available at http://www.eclipse.org/legal/epl-v10.html
8 package org.opendaylight.yangtools.yang.data.api.schema.stream;
10 import static com.google.common.base.Verify.verify;
11 import static java.util.Objects.requireNonNull;
12 import static org.opendaylight.yangtools.yang.data.api.schema.stream.NormalizedNodeStreamWriter.UNKNOWN_SIZE;
14 import com.google.common.annotations.Beta;
15 import com.google.common.collect.Iterables;
16 import java.io.Closeable;
17 import java.io.Flushable;
18 import java.io.IOException;
19 import java.util.Collection;
21 import javax.xml.stream.XMLStreamReader;
22 import javax.xml.transform.dom.DOMSource;
23 import org.eclipse.jdt.annotation.NonNull;
24 import org.opendaylight.yangtools.yang.common.QName;
25 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeIdentifier;
26 import org.opendaylight.yangtools.yang.data.api.schema.AnydataNode;
27 import org.opendaylight.yangtools.yang.data.api.schema.AnyxmlNode;
28 import org.opendaylight.yangtools.yang.data.api.schema.ChoiceNode;
29 import org.opendaylight.yangtools.yang.data.api.schema.ContainerNode;
30 import org.opendaylight.yangtools.yang.data.api.schema.DataContainerChild;
31 import org.opendaylight.yangtools.yang.data.api.schema.LeafNode;
32 import org.opendaylight.yangtools.yang.data.api.schema.LeafSetEntryNode;
33 import org.opendaylight.yangtools.yang.data.api.schema.MapEntryNode;
34 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
35 import org.opendaylight.yangtools.yang.data.api.schema.SystemLeafSetNode;
36 import org.opendaylight.yangtools.yang.data.api.schema.SystemMapNode;
37 import org.opendaylight.yangtools.yang.data.api.schema.UnkeyedListEntryNode;
38 import org.opendaylight.yangtools.yang.data.api.schema.UnkeyedListNode;
39 import org.opendaylight.yangtools.yang.data.api.schema.UserLeafSetNode;
40 import org.opendaylight.yangtools.yang.data.api.schema.UserMapNode;
41 import org.slf4j.Logger;
42 import org.slf4j.LoggerFactory;
45 * This is an experimental iterator over a {@link NormalizedNode}. This is essentially
46 * the opposite of a {@link XMLStreamReader} -- unlike instantiating an iterator over
47 * the backing data, this encapsulates a {@link NormalizedNodeStreamWriter} and allows
48 * us to write multiple nodes.
51 public class NormalizedNodeWriter implements Closeable, Flushable {
52 private static final Logger LOG = LoggerFactory.getLogger(NormalizedNodeWriter.class);
54 private final @NonNull NormalizedNodeStreamWriter writer;
56 protected NormalizedNodeWriter(final NormalizedNodeStreamWriter writer) {
57 this.writer = requireNonNull(writer);
60 protected final NormalizedNodeStreamWriter getWriter() {
65 * Create a new writer backed by a {@link NormalizedNodeStreamWriter}.
67 * @param writer Back-end writer
68 * @return A new instance.
70 public static NormalizedNodeWriter forStreamWriter(final NormalizedNodeStreamWriter writer) {
71 return forStreamWriter(writer, true);
75 * Create a new writer backed by a {@link NormalizedNodeStreamWriter}. Unlike the simple
76 * {@link #forStreamWriter(NormalizedNodeStreamWriter)} method, this allows the caller to switch off RFC6020 XML
77 * compliance, providing better throughput. The reason is that the XML mapping rules in RFC6020 require
78 * the encoding to emit leaf nodes which participate in a list's key first and in the order in which they are
79 * defined in the key. For JSON, this requirement is completely relaxed and leaves can be ordered in any way we
80 * see fit. The former requires a bit of work: first a lookup for each key and then for each emitted node we need
81 * to check whether it was already emitted.
83 * @param writer Back-end writer
84 * @param orderKeyLeaves whether the returned instance should be RFC6020 XML compliant.
85 * @return A new instance.
87 public static NormalizedNodeWriter forStreamWriter(final NormalizedNodeStreamWriter writer,
88 final boolean orderKeyLeaves) {
89 return orderKeyLeaves ? new OrderedNormalizedNodeWriter(writer) : new NormalizedNodeWriter(writer);
93 * Iterate over the provided {@link NormalizedNode} and emit write
94 * events to the encapsulated {@link NormalizedNodeStreamWriter}.
97 * @return NormalizedNodeWriter this
98 * @throws IOException when thrown from the backing writer.
100 public NormalizedNodeWriter write(final NormalizedNode node) throws IOException {
101 if (wasProcessedAsCompositeNode(node)) {
105 if (wasProcessAsSimpleNode(node)) {
109 throw new IllegalStateException("It wasn't possible to serialize node " + node);
113 public void flush() throws IOException {
118 public void close() throws IOException {
124 * Emit a best guess of a hint for a particular set of children. It evaluates the
125 * iterable to see if the size can be easily gotten to. If it is, we hint at the
126 * real number of child nodes. Otherwise we emit UNKNOWN_SIZE.
128 * @param children Child nodes
129 * @return Best estimate of the collection size required to hold all the children.
131 protected static int childSizeHint(final Iterable<?> children) {
132 return children instanceof Collection ? ((Collection<?>) children).size() : UNKNOWN_SIZE;
135 protected boolean wasProcessAsSimpleNode(final NormalizedNode node) throws IOException {
136 if (node instanceof LeafSetEntryNode<?> nodeAsLeafList) {
137 writer.startLeafSetEntryNode(nodeAsLeafList.getIdentifier());
138 writer.scalarValue(nodeAsLeafList.body());
141 } else if (node instanceof LeafNode<?> nodeAsLeaf) {
142 writer.startLeafNode(nodeAsLeaf.getIdentifier());
143 writer.scalarValue(nodeAsLeaf.body());
146 } else if (node instanceof AnyxmlNode<?> anyxmlNode) {
147 final Class<?> model = anyxmlNode.bodyObjectModel();
148 if (writer.startAnyxmlNode(anyxmlNode.getIdentifier(), model)) {
149 final Object value = node.body();
150 if (DOMSource.class.isAssignableFrom(model)) {
151 verify(value instanceof DOMSource, "Inconsistent anyxml node %s", anyxmlNode);
152 writer.domSourceValue((DOMSource) value);
154 writer.scalarValue(value);
160 LOG.debug("Ignoring unhandled anyxml node {}", anyxmlNode);
161 } else if (node instanceof AnydataNode<?> anydata) {
162 final Class<?> model = anydata.bodyObjectModel();
163 if (writer.startAnydataNode(anydata.getIdentifier(), model)) {
164 writer.scalarValue(anydata.body());
169 LOG.debug("Writer {} does not support anydata in form of {}", writer, model);
176 * Emit events for all children and then emit an endNode() event.
178 * @param children Child iterable
180 * @throws IOException when the writer reports it
182 protected boolean writeChildren(final Iterable<? extends NormalizedNode> children) throws IOException {
183 for (final NormalizedNode child : children) {
191 protected boolean writeMapEntryNode(final MapEntryNode node) throws IOException {
192 writer.startMapEntryNode(node.getIdentifier(), childSizeHint(node.body()));
193 return writeChildren(node.body());
196 protected boolean wasProcessedAsCompositeNode(final NormalizedNode node) throws IOException {
197 if (node instanceof ContainerNode n) {
198 writer.startContainerNode(n.getIdentifier(), childSizeHint(n.body()));
199 return writeChildren(n.body());
200 } else if (node instanceof MapEntryNode n) {
201 return writeMapEntryNode(n);
202 } else if (node instanceof UnkeyedListEntryNode n) {
203 writer.startUnkeyedListItem(n.getIdentifier(), childSizeHint(n.body()));
204 return writeChildren(n.body());
205 } else if (node instanceof ChoiceNode n) {
206 writer.startChoiceNode(n.getIdentifier(), childSizeHint(n.body()));
207 return writeChildren(n.body());
208 } else if (node instanceof UnkeyedListNode n) {
209 writer.startUnkeyedList(n.getIdentifier(), childSizeHint(n.body()));
210 return writeChildren(n.body());
211 } else if (node instanceof UserMapNode n) {
212 writer.startOrderedMapNode(n.getIdentifier(), childSizeHint(n.body()));
213 return writeChildren(n.body());
214 } else if (node instanceof SystemMapNode n) {
215 writer.startMapNode(n.getIdentifier(), childSizeHint(n.body()));
216 return writeChildren(n.body());
217 } else if (node instanceof UserLeafSetNode<?> n) {
218 writer.startOrderedLeafSet(n.getIdentifier(), childSizeHint(n.body()));
219 return writeChildren(n.body());
220 } else if (node instanceof SystemLeafSetNode<?> n) {
221 writer.startLeafSet(n.getIdentifier(), childSizeHint(n.body()));
222 return writeChildren(n.body());
227 private static final class OrderedNormalizedNodeWriter extends NormalizedNodeWriter {
228 private static final Logger LOG = LoggerFactory.getLogger(OrderedNormalizedNodeWriter.class);
230 OrderedNormalizedNodeWriter(final NormalizedNodeStreamWriter writer) {
235 protected boolean writeMapEntryNode(final MapEntryNode node) throws IOException {
236 final NormalizedNodeStreamWriter nnWriter = getWriter();
237 nnWriter.startMapEntryNode(node.getIdentifier(), childSizeHint(node.body()));
239 final Set<QName> qnames = node.getIdentifier().keySet();
240 // Write out all the key children
241 for (final QName qname : qnames) {
242 final DataContainerChild child = node.childByArg(new NodeIdentifier(qname));
246 LOG.info("No child for key element {} found", qname);
250 // Write all the rest
251 return writeChildren(Iterables.filter(node.body(), input -> {
252 if (qnames.contains(input.getIdentifier().getNodeType())) {
253 LOG.debug("Skipping key child {}", input);