1 package org.opendaylight.yangtools.yang.data.impl.codec.xml;
3 import com.google.common.annotations.Beta;
4 import com.google.common.annotations.VisibleForTesting;
5 import com.google.common.base.Preconditions;
9 import java.util.Map.Entry;
11 import javax.annotation.Nonnull;
12 import javax.annotation.Nullable;
13 import javax.xml.stream.XMLStreamException;
14 import javax.xml.stream.XMLStreamWriter;
16 import org.opendaylight.yangtools.yang.common.QName;
17 import org.opendaylight.yangtools.yang.data.api.AttributesContainer;
18 import org.opendaylight.yangtools.yang.data.api.CompositeNode;
19 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
20 import org.opendaylight.yangtools.yang.data.api.Node;
21 import org.opendaylight.yangtools.yang.data.api.SimpleNode;
22 import org.opendaylight.yangtools.yang.data.impl.codec.TypeDefinitionAwareCodec;
23 import org.opendaylight.yangtools.yang.data.impl.schema.SchemaUtils;
24 import org.opendaylight.yangtools.yang.model.api.DataNodeContainer;
25 import org.opendaylight.yangtools.yang.model.api.DataSchemaNode;
26 import org.opendaylight.yangtools.yang.model.api.LeafListSchemaNode;
27 import org.opendaylight.yangtools.yang.model.api.LeafSchemaNode;
28 import org.opendaylight.yangtools.yang.model.api.SchemaNode;
29 import org.opendaylight.yangtools.yang.model.api.TypeDefinition;
30 import org.opendaylight.yangtools.yang.model.api.type.IdentityrefTypeDefinition;
31 import org.opendaylight.yangtools.yang.model.api.type.InstanceIdentifierTypeDefinition;
32 import org.slf4j.Logger;
33 import org.slf4j.LoggerFactory;
36 * Utility class for bridging JAXP Stream and YANG Data APIs. Note that the definition of this class
37 * by no means final and subject to change as more functionality is centralized here.
40 public class XmlStreamUtils {
41 private static final Logger LOG = LoggerFactory.getLogger(XmlStreamUtils.class);
42 private final XmlCodecProvider codecProvider;
44 protected XmlStreamUtils(final XmlCodecProvider codecProvider) {
45 this.codecProvider = Preconditions.checkNotNull(codecProvider);
49 * Create a new instance encapsulating a particular codec provider.
51 * @param codecProvider XML codec provider
52 * @return A new instance
54 public static XmlStreamUtils create(final XmlCodecProvider codecProvider) {
55 return new XmlStreamUtils(codecProvider);
59 * Check if a particular data element can be emitted as an empty element, bypassing value encoding. This
60 * functionality is optional, as valid XML stream is produced even if start/end element is produced unconditionally.
62 * @param data Data node
63 * @return True if the data node will result in empty element body.
65 public static boolean isEmptyElement(final Node<?> data) {
70 if (data instanceof CompositeNode) {
71 return ((CompositeNode) data).getValue().isEmpty();
73 if (data instanceof SimpleNode) {
74 return data.getValue() == null;
82 * Write an InstanceIdentifier into the output stream. Calling corresponding {@link XMLStreamWriter#writeStartElement(String)}
83 * and {@link XMLStreamWriter#writeEndElement()} is the responsibility of the caller.
85 * @param writer XML Stream writer
86 * @param id InstanceIdentifier
87 * @throws XMLStreamException
89 public static void write(final @Nonnull XMLStreamWriter writer, final @Nonnull YangInstanceIdentifier id) throws XMLStreamException {
90 Preconditions.checkNotNull(writer, "Writer may not be null");
91 Preconditions.checkNotNull(id, "Variable should contain instance of instance identifier and can't be null");
93 final RandomPrefix prefixes = new RandomPrefix();
94 final String str = XmlUtils.encodeIdentifier(prefixes, id);
96 for (Entry<URI, String> e: prefixes.getPrefixes()) {
97 writer.writeNamespace(e.getValue(), e.getKey().toString());
99 writer.writeCharacters(str);
103 * Write a full XML document corresponding to a CompositeNode into an XML stream writer.
105 * @param writer XML Stream writer
106 * @param data data node
107 * @param schema corresponding schema node, may be null
108 * @throws XMLStreamException if an encoding problem occurs
110 public void writeDocument(final @Nonnull XMLStreamWriter writer, final @Nonnull CompositeNode data, final @Nullable SchemaNode schema) throws XMLStreamException {
111 // final Boolean repairing = (Boolean) writer.getProperty(XMLOutputFactory.IS_REPAIRING_NAMESPACES);
112 // Preconditions.checkArgument(repairing == true, "XML Stream Writer has to be repairing namespaces");
114 writer.writeStartDocument();
115 writeElement(writer, data, schema);
116 writer.writeEndDocument();
121 * Short-hand for {@link #writeDataDocument(XMLStreamWriter, CompositeNode, SchemaNode, XmlCodecProvider)} with
124 * @param writer XML Stream writer
125 * @param data data node
126 * @param schema corresponding schema node, may be null
127 * @throws XMLStreamException if an encoding problem occurs
129 public void writeDocument(final XMLStreamWriter writer, final CompositeNode data) throws XMLStreamException {
130 writeDocument(writer, data, null);
134 * Write an element into a XML stream writer. This includes the element start/end tags and
135 * the value of the element.
137 * @param writer XML Stream writer
138 * @param data data node
139 * @param schema Schema node
140 * @throws XMLStreamException if an encoding problem occurs
142 public void writeElement(final XMLStreamWriter writer, final @Nonnull Node<?> data, final SchemaNode schema) throws XMLStreamException {
143 final QName qname = data.getNodeType();
144 final String pfx = qname.getPrefix() != null ? qname.getPrefix() : "";
145 final String ns = qname.getNamespace() != null ? qname.getNamespace().toString() : "";
147 if (isEmptyElement(data)) {
148 writer.writeEmptyElement(pfx, qname.getLocalName(), ns);
152 writer.writeStartElement(pfx, qname.getLocalName(), ns);
153 if (data instanceof AttributesContainer && ((AttributesContainer) data).getAttributes() != null) {
154 RandomPrefix randomPrefix = new RandomPrefix();
155 for (Entry<QName, String> attribute : ((AttributesContainer) data).getAttributes().entrySet()) {
156 writeAttribute(writer, attribute, randomPrefix);
160 if (data instanceof SimpleNode<?>) {
162 if (schema instanceof LeafListSchemaNode) {
163 writeValue(writer, ((LeafListSchemaNode) schema).getType(), data.getValue());
164 } else if (schema instanceof LeafSchemaNode) {
165 writeValue(writer, ((LeafSchemaNode) schema).getType(), data.getValue());
167 Object value = data.getValue();
169 writer.writeCharacters(String.valueOf(value));
174 for (Node<?> child : ((CompositeNode) data).getValue()) {
175 DataSchemaNode childSchema = null;
176 if (schema instanceof DataNodeContainer) {
177 childSchema = SchemaUtils.findFirstSchema(child.getNodeType(), ((DataNodeContainer) schema).getChildNodes()).orNull();
178 if (LOG.isDebugEnabled()) {
179 if (childSchema == null) {
180 LOG.debug("Probably the data node \"{}\" does not conform to schema", child == null ? "" : child.getNodeType().getLocalName());
185 writeElement(writer, child, childSchema);
189 writer.writeEndElement();
193 static void writeAttribute(final XMLStreamWriter writer, final Entry<QName, String> attribute, final RandomPrefix randomPrefix)
194 throws XMLStreamException {
195 final QName key = attribute.getKey();
196 final String prefix = randomPrefix.encodePrefix(key);
197 writer.writeAttribute("xmlns:" + prefix, key.getNamespace().toString());
198 writer.writeAttribute(prefix, key.getNamespace().toString(), key.getLocalName(), attribute.getValue());
202 * Write a value into a XML stream writer. This method assumes the start and end of element is
203 * emitted by the caller.
205 * @param writer XML Stream writer
206 * @param data data node
207 * @param schema Schema node
208 * @throws XMLStreamException if an encoding problem occurs
210 public void writeValue(final @Nonnull XMLStreamWriter writer, final @Nonnull TypeDefinition<?> type, final Object value) throws XMLStreamException {
212 LOG.debug("Value of {}:{} is null, not encoding it", type.getQName().getNamespace(), type.getQName().getLocalName());
216 final TypeDefinition<?> baseType = XmlUtils.resolveBaseTypeFrom(type);
217 if (baseType instanceof IdentityrefTypeDefinition) {
218 write(writer, (IdentityrefTypeDefinition) baseType, value);
219 } else if (baseType instanceof InstanceIdentifierTypeDefinition) {
220 write(writer, (InstanceIdentifierTypeDefinition) baseType, value);
222 final TypeDefinitionAwareCodec<Object, ?> codec = codecProvider.codecFor(baseType);
226 text = codec.serialize(value);
227 } catch (ClassCastException e) {
228 LOG.error("Provided node value {} did not have type {} required by mapping. Using stream instead.", value, baseType, e);
229 text = String.valueOf(value);
232 LOG.error("Failed to find codec for {}, falling back to using stream", baseType);
233 text = String.valueOf(value);
235 writer.writeCharacters(text);
239 private static void write(final @Nonnull XMLStreamWriter writer, final @Nonnull IdentityrefTypeDefinition type, final @Nonnull Object value) throws XMLStreamException {
240 if (value instanceof QName) {
241 final QName qname = (QName) value;
243 if (qname.getPrefix() != null && !qname.getPrefix().isEmpty()) {
244 prefix = qname.getPrefix();
249 writer.writeNamespace(prefix, qname.getNamespace().toString());
250 writer.writeCharacters(prefix + ':' + qname.getLocalName());
252 LOG.debug("Value of {}:{} is not a QName but {}", type.getQName().getNamespace(), type.getQName().getLocalName(), value.getClass());
253 writer.writeCharacters(String.valueOf(value));
257 private static void write(final @Nonnull XMLStreamWriter writer, final @Nonnull InstanceIdentifierTypeDefinition type, final @Nonnull Object value) throws XMLStreamException {
258 if (value instanceof YangInstanceIdentifier) {
259 write(writer, (YangInstanceIdentifier)value);
261 LOG.debug("Value of {}:{} is not an InstanceIdentifier but {}", type.getQName().getNamespace(), type.getQName().getLocalName(), value.getClass());
262 writer.writeCharacters(String.valueOf(value));