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.impl.codec.xml;
10 import com.google.common.base.Preconditions;
11 import com.google.common.base.Strings;
12 import java.io.IOException;
13 import java.io.StringWriter;
15 import javax.xml.XMLConstants;
16 import javax.xml.namespace.NamespaceContext;
17 import javax.xml.stream.XMLStreamException;
18 import javax.xml.stream.XMLStreamWriter;
19 import javax.xml.transform.OutputKeys;
20 import javax.xml.transform.Transformer;
21 import javax.xml.transform.TransformerException;
22 import javax.xml.transform.TransformerFactory;
23 import javax.xml.transform.TransformerFactoryConfigurationError;
24 import javax.xml.transform.dom.DOMSource;
25 import javax.xml.transform.stax.StAXResult;
26 import javax.xml.transform.stream.StreamResult;
27 import org.opendaylight.yangtools.yang.common.QName;
28 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.AugmentationIdentifier;
29 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeIdentifier;
30 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeIdentifierWithPredicates;
31 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.PathArgument;
32 import org.opendaylight.yangtools.yang.data.api.schema.stream.NormalizedNodeStreamAttributeWriter;
33 import org.opendaylight.yangtools.yang.data.api.schema.stream.NormalizedNodeStreamWriter;
34 import org.opendaylight.yangtools.yang.data.impl.codec.SchemaTracker;
35 import org.opendaylight.yangtools.yang.model.api.AnyXmlSchemaNode;
36 import org.opendaylight.yangtools.yang.model.api.ContainerSchemaNode;
37 import org.opendaylight.yangtools.yang.model.api.LeafListSchemaNode;
38 import org.opendaylight.yangtools.yang.model.api.LeafSchemaNode;
39 import org.opendaylight.yangtools.yang.model.api.ListSchemaNode;
40 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
41 import org.opendaylight.yangtools.yang.model.api.SchemaNode;
42 import org.opendaylight.yangtools.yang.model.api.SchemaPath;
43 import org.w3c.dom.Element;
46 * A {@link NormalizedNodeStreamWriter} which translates the events into an
47 * {@link XMLStreamWriter}, resulting in a RFC 6020 XML encoding.
49 public final class XMLStreamNormalizedNodeStreamWriter implements NormalizedNodeStreamAttributeWriter {
51 private static final TransformerFactory TRANSFORMER_FACTORY = TransformerFactory.newInstance();
53 private final XMLStreamWriter writer;
54 private final SchemaTracker tracker;
55 private final XmlStreamUtils streamUtils;
56 private final RandomPrefix randomPrefix;
58 private XMLStreamNormalizedNodeStreamWriter(final XMLStreamWriter writer, final SchemaContext context, final SchemaPath path) {
59 this.writer = Preconditions.checkNotNull(writer);
60 this.tracker = SchemaTracker.create(context, path);
61 this.streamUtils = XmlStreamUtils.create(XmlUtils.DEFAULT_XML_CODEC_PROVIDER, context);
62 randomPrefix = new RandomPrefix();
66 * Create a new writer with the specified context as its root.
68 * @param writer Output {@link XMLStreamWriter}
69 * @param context Associated {@link SchemaContext}.
70 * @return A new {@link NormalizedNodeStreamWriter}
72 public static NormalizedNodeStreamWriter create(final XMLStreamWriter writer, final SchemaContext context) {
73 return create( writer, context, SchemaPath.ROOT);
77 * Create a new writer with the specified context and rooted in the specified schema path
79 * @param writer Output {@link XMLStreamWriter}
80 * @param context Associated {@link SchemaContext}.
83 * @return A new {@link NormalizedNodeStreamWriter}
85 public static NormalizedNodeStreamWriter create(final XMLStreamWriter writer, final SchemaContext context, final SchemaPath path) {
86 return new XMLStreamNormalizedNodeStreamWriter(writer, context, path);
89 private void writeStartElement(final QName qname) throws XMLStreamException {
90 String ns = qname.getNamespace().toString();
91 writer.writeStartElement(XMLConstants.DEFAULT_NS_PREFIX, qname.getLocalName(), ns);
92 if(writer.getNamespaceContext() != null) {
93 String parentNs = writer.getNamespaceContext().getNamespaceURI(XMLConstants.DEFAULT_NS_PREFIX);
94 if (!ns.equals(parentNs)) {
95 writer.writeDefaultNamespace(ns);
100 private void writeElement(final QName qname, final SchemaNode schemaNode, final Object value) throws IOException {
102 writeStartElement(qname);
104 streamUtils.writeValue(writer, schemaNode, value, qname.getModule());
106 writer.writeEndElement();
107 } catch (XMLStreamException e) {
108 throw new IOException("Failed to emit element", e);
112 private void writeElement(final QName qname, final SchemaNode schemaNode, final Object value, final Map<QName, String> attributes) throws IOException {
114 writeStartElement(qname);
116 writeAttributes(attributes);
118 streamUtils.writeValue(writer, schemaNode, value, qname.getModule());
120 writer.writeEndElement();
121 } catch (XMLStreamException e) {
122 throw new IOException("Failed to emit element", e);
126 private void startElement(final QName qname) throws IOException {
128 writeStartElement(qname);
129 } catch (XMLStreamException e) {
130 throw new IOException("Failed to start element", e);
134 private void startList(final NodeIdentifier name) {
135 tracker.startList(name);
138 private void startListItem(final PathArgument name) throws IOException {
139 tracker.startListItem(name);
140 startElement(name.getNodeType());
144 public void leafNode(final NodeIdentifier name, final Object value) throws IOException {
145 final LeafSchemaNode schema = tracker.leafNode(name);
146 writeElement(schema.getQName(), schema, value);
150 public void leafNode(final NodeIdentifier name, final Object value, final Map<QName, String> attributes) throws IOException {
151 final LeafSchemaNode schema = tracker.leafNode(name);
152 writeElement(schema.getQName(), schema, value, attributes);
156 public void leafSetEntryNode(final QName name, final Object value, final Map<QName, String> attributes) throws IOException {
157 final LeafListSchemaNode schema = tracker.leafSetEntryNode();
158 writeElement(schema.getQName(), schema, value, attributes);
162 public void startContainerNode(final NodeIdentifier name, final int childSizeHint, final Map<QName, String> attributes) throws IOException {
163 startContainerNode(name, childSizeHint);
164 writeAttributes(attributes);
168 public void startYangModeledAnyXmlNode(final NodeIdentifier name, final int childSizeHint, final Map<QName, String> attributes) throws IOException {
169 startYangModeledAnyXmlNode(name, childSizeHint);
170 writeAttributes(attributes);
174 public void startUnkeyedListItem(final NodeIdentifier name, final int childSizeHint, final Map<QName, String> attributes) throws IOException {
175 startUnkeyedListItem(name, childSizeHint);
176 writeAttributes(attributes);
180 public void startMapEntryNode(final NodeIdentifierWithPredicates identifier, final int childSizeHint, final Map<QName, String> attributes) throws IOException {
181 startMapEntryNode(identifier, childSizeHint);
182 writeAttributes(attributes);
185 private void writeAttributes(final Map<QName, String> attributes) throws IOException {
186 for (final Map.Entry<QName, String> qNameStringEntry : attributes.entrySet()) {
188 final String namespace = qNameStringEntry.getKey().getNamespace().toString();
190 if(Strings.isNullOrEmpty(namespace)) {
191 writer.writeAttribute(qNameStringEntry.getKey().getLocalName(), qNameStringEntry.getValue());
193 final String prefix = randomPrefix.encodePrefix(qNameStringEntry.getKey().getNamespace());
194 writer.writeAttribute(prefix, namespace, qNameStringEntry.getKey().getLocalName(), qNameStringEntry.getValue());
196 } catch (final XMLStreamException e) {
197 throw new IOException("Unable to emit attribute " + qNameStringEntry, e);
203 public void startLeafSet(final NodeIdentifier name, final int childSizeHint) {
204 tracker.startLeafSet(name);
208 public void leafSetEntryNode(final QName name, final Object value) throws IOException {
209 final LeafListSchemaNode schema = tracker.leafSetEntryNode();
210 writeElement(schema.getQName(), schema, value);
214 public void startOrderedLeafSet(final NodeIdentifier name, final int childSizeHint) {
215 tracker.startLeafSet(name);
219 public void startContainerNode(final NodeIdentifier name, final int childSizeHint) throws IOException {
220 final SchemaNode schema = tracker.startContainerNode(name);
221 startElement(schema.getQName());
225 public void startUnkeyedList(final NodeIdentifier name, final int childSizeHint) {
230 public void startUnkeyedListItem(final NodeIdentifier name, final int childSizeHint) throws IOException {
235 public void startMapNode(final NodeIdentifier name, final int childSizeHint) {
240 public void startMapEntryNode(final NodeIdentifierWithPredicates identifier, final int childSizeHint) throws IOException {
241 startListItem(identifier);
245 public void startOrderedMapNode(final NodeIdentifier name, final int childSizeHint) {
250 public void startChoiceNode(final NodeIdentifier name, final int childSizeHint) {
251 tracker.startChoiceNode(name);
255 public void startAugmentationNode(final AugmentationIdentifier identifier) {
256 tracker.startAugmentationNode(identifier);
260 public void anyxmlNode(final NodeIdentifier name, final Object value) throws IOException {
261 final AnyXmlSchemaNode schema = tracker.anyxmlNode(name);
263 Preconditions.checkArgument(value instanceof DOMSource, "AnyXML value must be DOMSource, not %s", value);
264 final QName qname = schema.getQName();
265 final DOMSource domSource = (DOMSource) value;
266 Preconditions.checkNotNull(domSource.getNode());
267 Preconditions.checkArgument(domSource.getNode().getNodeName().equals(qname.getLocalName()));
268 Preconditions.checkArgument(domSource.getNode().getNamespaceURI().equals(qname.getNamespace().toString()));
270 // TODO can the transformer be a constant ? is it thread safe ?
271 final Transformer transformer = TRANSFORMER_FACTORY.newTransformer();
272 // Writer has to be wrapped in a wrapper that ignores endDocument event
273 // EndDocument event forbids any other modification to the writer so a nested anyXml breaks serialization
274 transformer.transform(domSource, new StAXResult(new DelegateWriterNoEndDoc(writer)));
275 } catch (final TransformerException e) {
276 throw new IOException("Unable to transform anyXml(" + name + ") value: " + value, e);
282 public void startYangModeledAnyXmlNode(final NodeIdentifier name, final int childSizeHint) throws IOException {
283 final SchemaNode schema = tracker.startYangModeledAnyXmlNode(name);
284 startElement(schema.getQName());
287 public static String toString(final Element xml) {
289 final Transformer transformer = TRANSFORMER_FACTORY.newTransformer();
290 transformer.setOutputProperty(OutputKeys.INDENT, "yes");
292 final StreamResult result = new StreamResult(new StringWriter());
293 final DOMSource source = new DOMSource(xml);
294 transformer.transform(source, result);
296 return result.getWriter().toString();
297 } catch (IllegalArgumentException | TransformerFactoryConfigurationError | TransformerException e) {
298 throw new RuntimeException("Unable to serialize xml element " + xml, e);
303 public void endNode() throws IOException {
304 final Object schema = tracker.endNode();
307 if (schema instanceof ListSchemaNode) {
308 // For lists, we only emit end element on the inner frame
309 final Object parent = tracker.getParent();
310 if (parent == schema) {
311 writer.writeEndElement();
313 } else if (schema instanceof ContainerSchemaNode) {
314 // Emit container end element
315 writer.writeEndElement();
317 } catch (XMLStreamException e) {
318 throw new IOException("Failed to end element", e);
323 public void close() throws IOException {
326 } catch (XMLStreamException e) {
327 throw new IOException("Failed to close writer", e);
332 public void flush() throws IOException {
335 } catch (XMLStreamException e) {
336 throw new IOException("Failed to flush writer", e);
341 * Delegate writer that ignores writeEndDocument event. Used for AnyXml serialization.
343 private static final class DelegateWriterNoEndDoc implements XMLStreamWriter {
344 private final XMLStreamWriter writer;
346 public DelegateWriterNoEndDoc(final XMLStreamWriter writer) {
347 this.writer = writer;
351 public void writeStartElement(final String localName) throws XMLStreamException {
352 writer.writeStartElement(localName);
356 public void writeStartElement(final String namespaceURI, final String localName) throws XMLStreamException {
357 writer.writeStartElement(namespaceURI, localName);
361 public void writeStartElement(final String prefix, final String localName, final String namespaceURI) throws XMLStreamException {
362 writer.writeStartElement(prefix, localName, namespaceURI);
366 public void writeEmptyElement(final String namespaceURI, final String localName) throws XMLStreamException {
367 writer.writeEmptyElement(namespaceURI, localName);
371 public void writeEmptyElement(final String prefix, final String localName, final String namespaceURI) throws XMLStreamException {
372 writer.writeEmptyElement(prefix, localName, namespaceURI);
376 public void writeEmptyElement(final String localName) throws XMLStreamException {
377 writer.writeEmptyElement(localName);
381 public void writeEndElement() throws XMLStreamException {
382 writer.writeEndElement();
387 public void writeEndDocument() throws XMLStreamException {
388 // End document is disabled
392 public void close() throws XMLStreamException {
397 public void flush() throws XMLStreamException {
402 public void writeAttribute(final String localName, final String value) throws XMLStreamException {
403 writer.writeAttribute(localName, value);
407 public void writeAttribute(final String prefix, final String namespaceURI, final String localName, final String value) throws XMLStreamException {
408 writer.writeAttribute(prefix, namespaceURI, localName, value);
412 public void writeAttribute(final String namespaceURI, final String localName, final String value) throws XMLStreamException {
413 writer.writeAttribute(namespaceURI, localName, value);
417 public void writeNamespace(final String prefix, final String namespaceURI) throws XMLStreamException {
418 // Workaround for default namespace
419 // If a namespace is not prefixed, it is is still treated as prefix namespace. This results in the NamespaceSupport class ignoring the namespace since xmlns is not a valid prefix
420 // Write the namespace at least as an attribute
421 // TODO this is a hotfix, the transformer itself should write namespaces passing the namespace in writeStartElement method
422 if (prefix.equals("xml") || prefix.equals("xmlns")) {
423 writer.writeAttribute(prefix, namespaceURI);
425 writer.writeNamespace(prefix, namespaceURI);
430 public void writeDefaultNamespace(final String namespaceURI) throws XMLStreamException {
431 writer.writeDefaultNamespace(namespaceURI);
435 public void writeComment(final String data) throws XMLStreamException {
436 writer.writeComment(data);
440 public void writeProcessingInstruction(final String target) throws XMLStreamException {
441 writer.writeProcessingInstruction(target);
445 public void writeProcessingInstruction(final String target, final String data) throws XMLStreamException {
446 writer.writeProcessingInstruction(target, data);
450 public void writeCData(final String data) throws XMLStreamException {
451 writer.writeCData(data);
455 public void writeDTD(final String dtd) throws XMLStreamException {
456 writer.writeDTD(dtd);
460 public void writeEntityRef(final String name) throws XMLStreamException {
461 writer.writeEntityRef(name);
465 public void writeStartDocument() throws XMLStreamException {
469 public void writeStartDocument(final String version) throws XMLStreamException {
473 public void writeStartDocument(final String encoding, final String version) throws XMLStreamException {
477 public void writeCharacters(final String text) throws XMLStreamException {
478 writer.writeCharacters(text);
482 public void writeCharacters(final char[] text, final int start, final int len) throws XMLStreamException {
483 writer.writeCharacters(text, start, len);
487 public String getPrefix(final String uri) throws XMLStreamException {
488 return writer.getPrefix(uri);
492 public void setPrefix(final String prefix, final String uri) throws XMLStreamException {
493 // Disabled since it causes exceptions in the underlying writer
497 public void setDefaultNamespace(final String uri) throws XMLStreamException {
498 writer.setDefaultNamespace(uri);
502 public void setNamespaceContext(final NamespaceContext context) throws XMLStreamException {
503 writer.setNamespaceContext(context);
507 public NamespaceContext getNamespaceContext() {
508 return writer.getNamespaceContext();
512 public Object getProperty(final String name) {
513 return writer.getProperty(name);