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An OSGi bundle for Saxon-HE
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// Copyright (c) 2013 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.expr;
import net.sf.saxon.Configuration;
import net.sf.saxon.Controller;
import net.sf.saxon.event.Receiver;
import net.sf.saxon.event.SequenceReceiver;
import net.sf.saxon.expr.instruct.ParameterSet;
import net.sf.saxon.expr.sort.GroupIterator;
import net.sf.saxon.lib.ParseOptions;
import net.sf.saxon.lib.StringCollator;
import net.sf.saxon.om.*;
import net.sf.saxon.regex.RegexIterator;
import net.sf.saxon.trace.InstructionInfo;
import net.sf.saxon.trans.Mode;
import net.sf.saxon.trans.NoDynamicContextException;
import net.sf.saxon.trans.Rule;
import net.sf.saxon.trans.XPathException;
import net.sf.saxon.value.DateTimeValue;
import java.io.Serializable;
import java.util.Collections;
import java.util.Iterator;
/**
* This class is an implementation of XPathContext used when evaluating constant sub-expressions at
* compile time.
*/
public class EarlyEvaluationContext implements XPathContext, Serializable {
private CollationMap collationMap;
private Configuration config;
/**
* Create an early evaluation context, used for evaluating constant expressions at compile time
* @param config the Saxon configuration
* @param map the available collations
*/
public EarlyEvaluationContext(Configuration config, CollationMap map) {
this.config = config;
collationMap = map;
}
/**
* Set a new output destination, supplying the output format details.
* Note that it is the caller's responsibility to close the Writer after use.
*
* @throws net.sf.saxon.trans.XPathException
* if any dynamic error occurs; and
* specifically, if an attempt is made to switch to a final output
* destination while writing a temporary tree or sequence
*/
public void changeOutputDestination(Receiver receiver, ParseOptions options) throws XPathException {
notAllowed();
}
/**
* Get the value of a local variable, identified by its slot number
*/
/*@Nullable*/ public Sequence evaluateLocalVariable(int slotnumber) {
notAllowed();
return null;
}
/**
* Get the calling XPathContext (the next one down the stack). This will be null if unknown, or
* if the bottom of the stack has been reached.
*/
public XPathContext getCaller() {
return null;
}
/**
* Get a named collation
*/
public StringCollator getCollation(String name) throws XPathException {
return collationMap.getNamedCollation(name);
}
/**
* Get the Configuration
*/
public Configuration getConfiguration() {
return config;
}
/**
* Get the context item
*
* @return the context item, or null if the context item is undefined
*/
public Item getContextItem() {
return null;
}
/**
* Get the Controller. May return null when running outside XSLT or XQuery
*/
public Controller getController() {
return null;
}
/**
* Get the current group iterator. This supports the current-group() and
* current-grouping-key() functions in XSLT 2.0
*
* @return the current grouped collection
*/
public GroupIterator getCurrentGroupIterator() {
notAllowed();
return null;
}
/**
* Get the current iterator.
* This encapsulates the context item, context position, and context size.
*
* @return the current iterator, or null if there is no current iterator
* (which means the context item, position, and size are undefined).
*/
public SequenceIterator getCurrentIterator() {
return null;
}
/**
* Get the current mode.
*
* @return the current mode
*/
public Mode getCurrentMode() {
notAllowed();
return null;
}
/**
* Get the current regex iterator. This supports the functionality of the regex-group()
* function in XSLT 2.0.
*
* @return the current regular expressions iterator
*/
public RegexIterator getCurrentRegexIterator() {
return null;
}
/**
* Get the current template. This is used to support xsl:apply-imports
*
* @return the current template
*/
public Rule getCurrentTemplateRule() {
return null;
}
/**
* Get the context size (the position of the last item in the current node list)
*
* @return the context size
* @throws net.sf.saxon.trans.XPathException
* if the context position is undefined
*/
public int getLast() throws XPathException {
XPathException err = new XPathException("The context item is absent");
err.setErrorCode("XPDY0002");
throw err;
}
/**
* Get the local (non-tunnel) parameters that were passed to the current function or template
*
* @return a ParameterSet containing the local parameters
*/
public ParameterSet getLocalParameters() {
notAllowed();
return null;
}
/**
* Get the Name Pool
*/
public NamePool getNamePool() {
return config.getNamePool();
}
/**
* Get information about the creating expression or other construct.
*/
public InstructionInfo getOrigin() {
return null;
}
/**
* Get the type of location from which this context was created.
*/
public int getOriginatingConstructType() {
return -1;
}
/**
* Get the Receiver to which output is currently being written.
*
* @return the current Receiver
*/
public SequenceReceiver getReceiver() {
notAllowed();
return null;
}
/**
* Get a reference to the local stack frame for variables. Note that it's
* the caller's job to make a local copy of this. This is used for creating
* a Closure containing a retained copy of the variables for delayed evaluation.
*
* @return array of variables.
*/
public StackFrame getStackFrame() {
notAllowed();
return null;
}
/**
* Get the tunnel parameters that were passed to the current function or template. This includes all
* active tunnel parameters whether the current template uses them or not.
*
* @return a ParameterSet containing the tunnel parameters
*/
public ParameterSet getTunnelParameters() {
notAllowed();
return null;
}
/**
* Determine whether the context position is the same as the context size
* that is, whether position()=last()
*/
public boolean isAtLast() throws XPathException {
XPathException err = new XPathException("The context item is absent");
err.setErrorCode("XPDY0002");
throw err;
}
/**
* Construct a new context without copying (used for the context in a function call)
*/
public XPathContextMajor newCleanContext() {
notAllowed();
return null;
}
/**
* Construct a new context as a copy of another. The new context is effectively added
* to the top of a stack, and contains a pointer to the previous context
*/
public XPathContextMajor newContext() {
Controller controller = new Controller(config);
return controller.newXPathContext();
// notAllowed();
// return null;
}
/**
* Construct a new minor context. A minor context can only hold new values of the focus
* (currentIterator) and current output destination.
*/
public XPathContextMinor newMinorContext() {
return newContext().newMinorContext();
// notAllowed();
// return null;
}
/**
* Set the calling XPathContext
*/
public void setCaller(XPathContext caller) {
// no-op
}
/**
* Set a new sequence iterator.
*/
public void setCurrentIterator(SequenceIterator iter) {
notAllowed();
}
/**
* Set the value of a local variable, identified by its slot number
*/
public void setLocalVariable(int slotnumber, Sequence value) {
notAllowed();
}
/**
* Change the Receiver to which output is written
*/
public void setReceiver(SequenceReceiver receiver) {
notAllowed();
}
/**
* Use local parameter. This is called when a local xsl:param element is processed.
* If a parameter of the relevant name was supplied, it is bound to the xsl:param element.
* Otherwise the method returns false, so the xsl:param default will be evaluated
*
* @param parameterId
* @param slotNumber
* @param isTunnel True if a tunnel parameter is required, else false @return true if a parameter of this name was supplied, false if not
*/
public int useLocalParameter(int parameterId, int slotNumber, boolean isTunnel) throws XPathException {
return ParameterSet.NOT_SUPPLIED;
}
/**
* Get the current date and time. This implementation always throws a
* NoDynamicContextException.
* @return the current date and time. All calls within a single query or transformation
* will return the same value
*/
public DateTimeValue getCurrentDateTime() throws NoDynamicContextException {
throw new NoDynamicContextException("current-dateTime");
}
/**
* Get the implicit timezone, as a positive or negative offset from UTC in minutes.
* The range is -14hours to +14hours. This implementation always throws a
* NoDynamicContextException.
* @return the implicit timezone, as an offset from UTC in minutes
*/
public int getImplicitTimezone() throws NoDynamicContextException{
throw new NoDynamicContextException("implicit-timezone");
}
/**
* Get the context stack. This method returns an iterator whose items are instances of
* {@link net.sf.saxon.trace.ContextStackFrame}, starting with the top-most stackframe and
* ending at the point the query or transformation was invoked by a calling application.
*
* @return an iterator over a copy of the run-time call stack
*/
public Iterator iterateStackFrames() {
return Collections.EMPTY_LIST.iterator();
}
/**
* Get the current exception (in saxon:catch)
* @return the current exception, or null if there is none defined
*/
public XPathException getCurrentException() {
return null;
}
public void notifyChildThreads() throws XPathException {
getCaller().notifyChildThreads();
}
/**
* Ask whether the XSLT output state is "temporary" or "final"
*
* @return true to set temporary output state; false to set final output state
*/
public boolean isTemporaryOutputState() {
return false;
}
/**
* Throw an error for operations that aren't supported when doing early evaluation of constant
* subexpressions
*/
private void notAllowed() {
throw new UnsupportedOperationException(
new NoDynamicContextException("Internal error: early evaluation of subexpression with no context"));
}
}