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////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// Copyright (c) 2018-2022 Saxonica Limited
// This Source Code Form is subject to the terms of the Mozilla Public License, v. 2.0.
// If a copy of the MPL was not distributed with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
// This Source Code Form is "Incompatible With Secondary Licenses", as defined by the Mozilla Public License, v. 2.0.
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
package net.sf.saxon.pattern;
import net.sf.saxon.om.*;
import net.sf.saxon.trace.ExpressionPresenter;
import net.sf.saxon.tree.tiny.NodeVectorTree;
import net.sf.saxon.type.*;
import net.sf.saxon.z.IntPredicateLambda;
import net.sf.saxon.z.IntPredicateProxy;
import net.sf.saxon.z.IntSet;
import net.sf.saxon.z.IntSingletonSet;
import java.util.Optional;
/**
* NodeTest is an interface that enables a test of whether a node has a particular
* name and type. A NameTest matches the node kind and the namespace URI and the local
* name. Note that unlike the XPath production called NameTest, this is a test for a specific
* name, and does not include wildcard matches.
*/
public class NameTest extends NodeTest implements QNameTest {
private final int nodeKind;
private final int fingerprint;
private final UType uType;
private final NamePool namePool;
/*@Nullable*/ private String uri = null; // the URI corresponding to the fingerprint - computed lazily
/*@Nullable*/ private String localName = null; //the local name corresponding to the fingerprint - computed lazily
/**
* Create a NameTest to match nodes by name
*
* @param nodeKind the kind of node, for example {@link Type#ELEMENT}
* @param uri the namespace URI of the required nodes. Supply "" to match nodes that are in
* no namespace
* @param localName the local name of the required nodes. Supply "" to match unnamed nodes
* @param namePool the namePool holding the name codes
* @since 9.0
*/
public NameTest(int nodeKind, String uri, String localName, NamePool namePool) {
this.uri = uri;
this.localName = localName;
this.nodeKind = nodeKind;
this.fingerprint = namePool.allocateFingerprint(uri, localName) & NamePool.FP_MASK;
this.namePool = namePool;
this.uType = UType.fromTypeCode(nodeKind);
}
/**
* Create a NameTest to match nodes by their nameCode allocated from the NamePool
*
* @param nodeKind the kind of node, for example {@link Type#ELEMENT}
* @param nameCode the nameCode representing the name of the node
* @param namePool the namePool holding the name codes
* @since 8.4
*/
public NameTest(int nodeKind, int nameCode, NamePool namePool) {
this.nodeKind = nodeKind;
this.fingerprint = nameCode & NamePool.FP_MASK;
this.namePool = namePool;
this.uType = UType.fromTypeCode(nodeKind);
}
/**
* Create a NameTest to match nodes by name
*
* @param nodeKind the kind of node, for example {@link Type#ELEMENT}
* @param name the name of the nodes that this NameTest will match
* @param pool the namePool holding the name codes
* @since 9.4
*/
public NameTest(int nodeKind, NodeName name, NamePool pool) {
this.uri = name.getURI();
this.localName = name.getLocalPart();
this.nodeKind = nodeKind;
this.fingerprint = name.obtainFingerprint(pool);
this.namePool = pool;
this.uType = UType.fromTypeCode(nodeKind);
}
/**
* Get the NamePool associated with this NameTest
*
* @return the NamePool
*/
public NamePool getNamePool() {
return namePool;
}
/**
* Get the node kind that this name test matches
*
* @return the matching node kind
*/
public int getNodeKind() {
return nodeKind;
}
/**
* Get the corresponding {@link net.sf.saxon.type.UType}. A UType is a union of primitive item
* types.
*
* @return the smallest UType that subsumes this item type
*/
@Override
public UType getUType() {
return uType;
}
/**
* Test whether this node test is satisfied by a given node. This method is only
* fully supported for a subset of NodeTests, because it doesn't provide all the information
* needed to evaluate all node tests. In particular (a) it can't be used to evaluate a node
* test of the form element(N,T) or schema-element(E) where it is necessary to know whether the
* node is nilled, and (b) it can't be used to evaluate a node test of the form
* document-node(element(X)). This in practice means that it is used (a) to evaluate the
* simple node tests found in the XPath 1.0 subset used in XML Schema, and (b) to evaluate
* node tests where the node kind is known to be an attribute.
*
* @param nodeKind The kind of node to be matched
* @param name identifies the expanded name of the node to be matched.
* The value should be null for a node with no name.
* @param annotation The actual content type of the node
*/
@Override
public boolean matches(int nodeKind, NodeName name, SchemaType annotation) {
if (nodeKind != this.nodeKind) {
return false;
}
if (name.hasFingerprint()) {
return name.getFingerprint() == this.fingerprint;
} else {
computeUriAndLocal();
return name.hasURI(uri) && name.getLocalPart().equals(localName);
}
}
@Override
public IntPredicateProxy getMatcher(final NodeVectorTree tree) {
final byte[] nodeKindArray = tree.getNodeKindArray();
final int[] nameCodeArray = tree.getNameCodeArray();
return IntPredicateLambda.of(nodeNr -> (nameCodeArray[nodeNr] & 0xfffff) == fingerprint &&
(nodeKindArray[nodeNr] & 0x0f) == nodeKind);
}
/**
* Test whether this node test is satisfied by a given node. This alternative
* method is used in the case of nodes where calculating the fingerprint is expensive,
* for example DOM or JDOM nodes.
*
* @param node the node to be matched
*/
@Override
public boolean test(NodeInfo node) {
if (node.getNodeKind() != nodeKind) {
return false;
}
// Two different algorithms are used for name matching. If the fingerprint of the node is readily
// available, we use it to do an integer comparison. Otherwise, we do string comparisons on the URI
// and local name. In practice, Saxon's native node implementations use fingerprint matching, while
// DOM and JDOM nodes use string comparison of names
if (node.hasFingerprint()) {
return node.getFingerprint() == fingerprint;
} else {
computeUriAndLocal();
return localName.equals(node.getLocalPart()) && uri.equals(node.getURI());
}
}
private void computeUriAndLocal() {
if (uri == null || localName == null) {
StructuredQName name = namePool.getUnprefixedQName(fingerprint);
uri = name.getURI();
localName = name.getLocalPart();
}
}
/**
* Test whether the NameTest matches a given QName
*
* @param qname the QName to be matched
* @return true if the name matches
*/
@Override
public boolean matches(StructuredQName qname) {
computeUriAndLocal();
return qname.getLocalPart().equals(localName) && qname.hasURI(uri);
}
/**
* Determine the default priority of this node test when used on its own as a Pattern
*/
@Override
public final double getDefaultPriority() {
return 0.0;
}
/**
* Get the fingerprint required
*/
@Override
public int getFingerprint() {
return fingerprint;
}
/**
* Get the name of the nodes matched by this nodetest, if it matches a specific name.
* Return null if the node test matches nodes of more than one name
*/
@Override
public StructuredQName getMatchingNodeName() {
computeUriAndLocal();
return new StructuredQName("", uri, localName);
}
/**
* Determine the types of nodes to which this pattern applies. Used for optimisation.
* For patterns that match nodes of several types, return Type.NODE
*
* @return the type of node matched by this pattern. e.g. Type.ELEMENT or Type.TEXT
*/
@Override
public int getPrimitiveType() {
return nodeKind;
}
/**
* Get the set of node names allowed by this NodeTest. This is returned as a set of Integer fingerprints.
* A null value indicates that all names are permitted (i.e. that there are no constraints on the node name.
* The default implementation returns null.
*/
/*@NotNull*/
@Override
public Optional getRequiredNodeNames() {
return Optional.of(new IntSingletonSet(fingerprint));
}
/**
* Get the namespace URI matched by this nametest
*
* @return the namespace URI (using "" for the "null namepace")
*/
public String getNamespaceURI() {
computeUriAndLocal();
return uri;
}
/**
* Get the local name matched by this nametest
*
* @return the local name
*/
public String getLocalPart() {
computeUriAndLocal();
return localName;
}
public String toString() {
switch (nodeKind) {
case Type.ELEMENT:
return "element(" + namePool.getEQName(fingerprint) + ")";
case Type.ATTRIBUTE:
return "attribute(" + namePool.getEQName(fingerprint) + ")";
case Type.PROCESSING_INSTRUCTION:
return "processing-instruction(" + namePool.getLocalName(fingerprint) + ')';
case Type.NAMESPACE:
return "namespace-node(" + namePool.getLocalName(fingerprint) + ')';
}
return namePool.getEQName(fingerprint);
}
/**
* Returns a hash code value for the object.
*/
public int hashCode() {
return nodeKind << 20 ^ fingerprint;
}
/**
* Determines whether two NameTests are equal
*/
public boolean equals(Object other) {
return other instanceof NameTest &&
((NameTest) other).namePool == namePool &&
((NameTest) other).nodeKind == nodeKind &&
((NameTest) other).fingerprint == fingerprint;
}
@Override
public String getFullAlphaCode() {
return getBasicAlphaCode() + " n" + getMatchingNodeName().getEQName();
}
/**
* Export the QNameTest as a string for use in a SEF file (typically in a catch clause).
*
* @return a string representation of the QNameTest, suitable for use in export files. The format is
* a sequence of alternatives separated by vertical bars, where each alternative is one of '*',
* '*:localname', 'Q{uri}*', or 'Q{uri}local'.
*/
@Override
public String exportQNameTest() {
return getMatchingNodeName().getEQName();
}
/**
* Generate Javascript code to test if a name matches the test.
*
* @return JS code as a string. The generated code will be used
* as the body of a JS function in which the argument name "q" is an
* XdmQName object holding the name. The XdmQName object has properties
* uri and local.
* @param targetVersion the version of Saxon-JS being targeted
*/
@Override
public String generateJavaScriptNameTest(int targetVersion) {
computeUriAndLocal();
return "q.uri==='" + ExpressionPresenter.jsEscape(uri) + "'&&q.local==='" + localName + "'";
}
/**
* Get extra diagnostic information about why a supplied item does not conform to this
* item type, if available. If extra information is returned, it should be in the form of a complete
* sentence, minus the closing full stop. No information should be returned for obvious cases.
*
* @param item the item that doesn't match this type
* @param th the type hierarchy cache
* @return optionally, a message explaining why the item does not match the type
*/
@Override
public Optional explainMismatch(Item item, TypeHierarchy th) {
Optional explanation = super.explainMismatch(item, th);
if (explanation.isPresent()) {
return explanation;
}
return Optional.of("The node has the wrong name");
}
@Override
public String toShortString() {
switch (nodeKind) {
case Type.ELEMENT:
return getNamespaceURI().isEmpty() ? namePool.getLocalName(getFingerprint()) : toString();
case Type.ATTRIBUTE:
return "@" + (getNamespaceURI().isEmpty() ? namePool.getLocalName(getFingerprint()) : toString());
default:
return toString();
}
}
}