net.sf.saxon.sxpath.XPathDynamicContext Maven / Gradle / Ivy
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// Copyright (c) 2015 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.sxpath;
import net.sf.saxon.expr.XPathContext;
import net.sf.saxon.expr.XPathContextMajor;
import net.sf.saxon.expr.instruct.SlotManager;
import net.sf.saxon.expr.parser.TypeChecker;
import net.sf.saxon.lib.CollectionFinder;
import net.sf.saxon.lib.CollectionURIResolver;
import net.sf.saxon.lib.UnfailingErrorListener;
import net.sf.saxon.lib.UnparsedTextURIResolver;
import net.sf.saxon.om.*;
import net.sf.saxon.trans.SaxonErrorCode;
import net.sf.saxon.trans.XPathException;
import net.sf.saxon.tree.iter.ManualIterator;
import net.sf.saxon.type.ItemType;
import net.sf.saxon.type.TypeHierarchy;
import net.sf.saxon.value.SequenceType;
import javax.xml.transform.ErrorListener;
import javax.xml.transform.URIResolver;
/**
* This object represents the dynamic XPath execution context for use in the free-standing Saxon XPath API.
* The dynamic context holds the context item and the values of external variables used by the XPath expression.
*
* This object is always created via the method
* {@link net.sf.saxon.sxpath.XPathExpression#createDynamicContext(net.sf.saxon.om.Item)}
*/
public class XPathDynamicContext {
private ItemType contextItemType;
private XPathContextMajor contextObject;
private SlotManager stackFrameMap;
protected XPathDynamicContext(ItemType contextItemType, XPathContextMajor contextObject, SlotManager stackFrameMap) {
this.contextItemType = contextItemType;
this.contextObject = contextObject;
this.stackFrameMap = stackFrameMap;
}
/**
* Set the context item for evaluation of the XPath Expression
*
* @param item the context item
* @throws XPathException if the node is in a document that was built under the wrong configuration
*/
public void setContextItem(Item item) throws XPathException {
if (item instanceof FingerprintedNode) {
if (!((FingerprintedNode) item).getConfiguration().isCompatible(contextObject.getConfiguration())) {
throw new XPathException(
"Supplied node must be built using the same or a compatible Configuration",
SaxonErrorCode.SXXP0004);
}
}
TypeHierarchy th = contextObject.getConfiguration().getTypeHierarchy();
if (!contextItemType.matches(item, th)) {
throw new XPathException("Supplied context item does not match required context item type " +
contextItemType.toString());
}
ManualIterator iter = new ManualIterator(item);
contextObject.setCurrentIterator(iter);
}
/**
* Get the context item
*
* @return the context item if there is one, or null otherwise
*/
public Item getContextItem() {
return contextObject.getContextItem();
}
/**
* Set the value of an external variable used within the XPath expression
*
* @param variable the object representing the variable.
* Note that setting the value of a variable does not modify the {@link XPathVariable}
* object itself, which means that this method is thread-safe.
* @param value The value of the variable.
* @throws XPathException if the supplied value does not conform to the required type of the
* variable; or if the supplied value contains a node that does not belong to this Configuration
* (or another Configuration that shares the same namePool)
*/
public void setVariable(XPathVariable variable, Sequence value) throws XPathException {
SequenceType requiredType = variable.getRequiredType();
if (requiredType != SequenceType.ANY_SEQUENCE) {
XPathException err = TypeChecker.testConformance(value, requiredType, contextObject);
if (err != null) {
throw err;
}
}
SequenceIterator iter = value.iterate();
Item item;
while ((item = iter.next()) != null) {
if (item instanceof FingerprintedNode && !((FingerprintedNode) item).getConfiguration().isCompatible(contextObject.getConfiguration())) {
throw new XPathException(
"Supplied node must be built using the same or a compatible Configuration",
SaxonErrorCode.SXXP0004);
}
}
int slot = variable.getLocalSlotNumber();
StructuredQName expectedName = slot >= stackFrameMap.getNumberOfVariables() ? null :
stackFrameMap.getVariableMap().get(slot);
if (!variable.getVariableQName().equals(expectedName)) {
throw new XPathException(
"Supplied XPathVariable is bound to the wrong slot: perhaps it was created using a different static context");
}
contextObject.setLocalVariable(slot, value);
}
/**
* Set an object that will be used to resolve URIs used in
* document(), etc. The URIResolver is set locally to this XPathContext
* object.
*
* @param resolver An object that implements the URIResolver interface, or
* null.
* @since 9.2. Changed in 9.6 to set the URIResolver locally.
*/
public void setURIResolver(URIResolver resolver) {
contextObject.setURIResolver(resolver);
}
/**
* Get the URI resolver.
*
* @return the user-supplied URI resolver if there is one, or null otherwise. If no URIResolver
* has been set locally, the URIResolver in the Controller is returned; this in turn defaults
* to the URIResolver set in the Configuration.
* @since 9.2. Changed in 9.6 to use a local URIResolver.
*/
public URIResolver getURIResolver() {
return contextObject.getURIResolver();
}
/**
* Set the CollectionURIResolver used for resolving collection URIs.
* Defaults to the CollectionURIResolver registered with the Configuration
*
* @param resolver the resolver for references to collections
* @since 9.4
* @deprecated since 9.7 - use {@link #setCollectionFinder(CollectionFinder)}
*/
public void setCollectionURIResolver(CollectionURIResolver resolver) {
contextObject.getController().setCollectionURIResolver(resolver);
}
/**
* Get the CollectionURIResolver used for resolving references to collections.
* If none has been set on the Controller, returns the
* CollectionURIResolver registered with the Configuration
*
* @return the resolver for references to collections
* @since 9.4
* @deprecated since 9.7 - use {@link #getCollectionFinder()}
*/
public CollectionURIResolver getCollectionURIResolver() {
return contextObject.getController().getCollectionURIResolver();
}
/**
* Get the collection finder associated with this configuration. This is used to dereference
* collection URIs used in the fn:collection and fn:uri-collection functions
*
* @return the CollectionFinder to be used
* @since 9.7
*/
public CollectionFinder getCollectionFinder() {
return contextObject.getController().getCollectionFinder();
}
/**
* Set the collection finder associated with this configuration. This is used to dereference
* collection URIs used in the fn:collection and fn:uri-collection functions
*
* @param cf the CollectionFinder to be used
* @since 9.7
*/
public void setCollectionFinder(CollectionFinder cf) {
contextObject.getController().setCollectionFinder(cf);
}
/**
* Set the error listener. The ErrorListener is set locally to this XPathContext
* object.
*
* @param listener the ErrorListener to be used
* @since 9.2. Changed in 9.6 to set the ErrorListener locally.
*/
public void setErrorListener(ErrorListener listener) {
contextObject.setErrorListener(listener);
}
/**
* Get the error listener. If no ErrorListener
* has been set locally, the ErrorListener in the Controller is returned; this in turn defaults
* to the ErrorListener set in the Configuration.
*
* @return the ErrorListener in use. This will always be an UnfailingErrorListener,
* which is a Saxon subclass of ErrorListener that throws no exceptions.
* @since 9.2. Changed in 9.6 to use a local ErrorListener.
*/
public UnfailingErrorListener getErrorListener() {
return contextObject.getErrorListener();
}
/**
* For system use: get the wrapped XPathContext object
*
* @return the underlying XPathContext object
*/
public XPathContext getXPathContextObject() {
return contextObject;
}
/**
* Set an object that will be used to resolve URIs used in
* fn:unparsed-text() and related functions.
*
* @param resolver An object that implements the UnparsedTextURIResolver interface, or
* null.
* @since 9.5
*/
public void setUnparsedTextURIResolver(UnparsedTextURIResolver resolver) {
contextObject.getController().setUnparsedTextURIResolver(resolver);
}
/**
* Get the URI resolver for unparsed text.
*
* @return the user-supplied unparsed text URI resolver if there is one, or the
* system-defined one otherwise
* @since 9.5
*/
public UnparsedTextURIResolver getUnparsedTextURIResolver() {
return contextObject.getController().getUnparsedTextURIResolver();
}
/**
* Check that all external variables have been given a value
*
* @param stackFrameMap describes the stack frame
* @param numberOfExternals the number of variables that need to be supplied
* @throws XPathException if required variables have not been given a value
*/
protected void checkExternalVariables(/*@NotNull*/ SlotManager stackFrameMap, int numberOfExternals) throws XPathException {
Sequence[] stack = contextObject.getStackFrame().getStackFrameValues();
for (int i = 0; i < numberOfExternals; i++) {
if (stack[i] == null) {
StructuredQName qname = stackFrameMap.getVariableMap().get(i);
throw new XPathException("No value has been supplied for variable $" + qname.getDisplayName());
}
}
}
}
© 2015 - 2025 Weber Informatics LLC | Privacy Policy