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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.trans;
import net.sf.saxon.expr.XPathContext;
import net.sf.saxon.expr.instruct.Template;
import net.sf.saxon.expr.parser.Optimizer;
import net.sf.saxon.expr.parser.Token;
import net.sf.saxon.om.Item;
import net.sf.saxon.om.StructuredQName;
import net.sf.saxon.pattern.*;
import net.sf.saxon.style.StylesheetModule;
import net.sf.saxon.trace.ExpressionPresenter;
import java.io.Serializable;
import java.util.Collection;
import java.util.HashMap;
/**
* RuleManager maintains a set of template rules, one set for each mode
* @version 10 December 1999: carved out of the old Controller class
* @author Michael H. Kay
*/
public final class RuleManager implements Serializable {
private Mode unnamedMode; // node handlers with default mode
private HashMap modes;
// tables of node handlers for non-default modes
private Mode omniMode = null; // node handlers that specify mode="all"
private int recoveryPolicy;
/**
* create a RuleManager and initialise variables.
*/
public RuleManager() {
resetHandlers();
}
/**
* Set the policy for handling recoverable errrors. Note that for some errors the decision can be
* made at run-time, but for the "ambiguous template match" error, the decision is (since 9.2)
* fixed at compile time.
* @param policy the recovery policy to be used. The options are {@link net.sf.saxon.Configuration#RECOVER_SILENTLY},
* {@link net.sf.saxon.Configuration#RECOVER_WITH_WARNINGS}, or {@link net.sf.saxon.Configuration#DO_NOT_RECOVER}.
* @since 9.2
*/
public void setRecoveryPolicy(int policy) {
recoveryPolicy = policy;
unnamedMode.setRecoveryPolicy(policy);
}
/**
* Get the policy for handling recoverable errors. Note that for some errors the decision can be
* made at run-time, but for the "ambiguous template match" error, the decision is (since 9.2)
* fixed at compile time.
*
* @return the current policy.
* @since 9.2
*/
public int getRecoveryPolicy() {
return recoveryPolicy;
}
/**
* Get all registered modes
* @return a collection containing all registered modes excluding the unnamed mode
*/
public Collection getAllNamedModes() {
return modes.values();
}
/**
* Set up a new table of handlers.
*/
public void resetHandlers() {
unnamedMode = new Mode(Mode.UNNAMED_MODE, Mode.UNNAMED_MODE_NAME);
unnamedMode.setRecoveryPolicy(recoveryPolicy);
modes = new HashMap(5);
}
/**
* Get the mode object for the unnamed mode
* @return the unnamed mode
*/
/*@NotNull*/
public Mode getUnnamedMode() {
return unnamedMode;
}
/**
* Get the Mode object for a named mode. If there is not one already registered.
* a new Mode is created.
* @param modeName The name of the mode. Supply null to get the default
* mode or Mode.ALL_MODES to get the Mode object containing "mode=all" rules
* @param createIfAbsent if true, then if the mode does not already exist it will be created.
* If false, then if the mode does not already exist the method returns null.
* @return the Mode with this name
*/
/*@Nullable*/ public Mode getMode(StructuredQName modeName, boolean createIfAbsent) {
if (modeName == null || modeName.equals(Mode.UNNAMED_MODE_NAME)) {
return unnamedMode;
}
if (modeName.equals(Mode.ALL_MODES)) {
if (omniMode==null) {
omniMode = new Mode(Mode.NAMED_MODE, modeName);
omniMode.setRecoveryPolicy(recoveryPolicy);
}
return omniMode;
}
//Integer modekey = new Integer(modeNameCode & 0xfffff);
Mode m = modes.get(modeName);
if (m == null && createIfAbsent) {
m = new Mode(omniMode, modeName);
m.setRecoveryPolicy(recoveryPolicy);
modes.put(modeName, m);
// when creating a specific mode, copy all the rules currently held
// in the omniMode, as these apply to all modes
}
return m;
}
/**
* Register a template for a particular pattern.
* @param pattern Must be a valid Pattern.
* @param eh The Template to be used
* @param mode The processing mode to which this template applies
* @param module The stylesheet module containing the template rule
* @param priority The priority of the rule: if an element matches several patterns, the
* one with highest priority is used
* @see Pattern
*/
public void setTemplateRule(Pattern pattern, Template eh,
Mode mode, StylesheetModule module, double priority) {
// for a union pattern, register the parts separately
// Note: technically this is only necessary if using default priorities and if the priorities
// of the two halves are different. However, splitting increases the chance that the pattern
// can be matched by hashing on the element name, so we do it always
if (pattern instanceof UnionPattern) {
UnionPattern up = (UnionPattern)pattern;
Pattern p1 = up.getLHS();
Pattern p2 = up.getRHS();
// Expression currentSetter = up.getVariableBindingExpression();
// if (currentSetter != null) {
// p1.setVariableBindingExpression(currentSetter);
// p2.setVariableBindingExpression(currentSetter);
// }
setTemplateRule(p1, eh, mode, module, priority);
setTemplateRule(p2, eh, mode, module, priority);
return;
}
// some union patterns end up as a CombinedNodeTest. Need to split these.
// (Same reasoning as above)
if (pattern instanceof ItemTypePattern &&
pattern.getItemType() instanceof CombinedNodeTest &&
((CombinedNodeTest)pattern.getItemType()).getOperator() == Token.UNION) {
CombinedNodeTest cnt = (CombinedNodeTest)pattern.getItemType();
NodeTest[] nt = cnt.getComponentNodeTests();
setTemplateRule(new ItemTypePattern(nt[0]), eh, mode, module, priority);
setTemplateRule(new ItemTypePattern(nt[1]), eh, mode, module, priority);
return;
}
if (Double.isNaN(priority)) {
priority = pattern.getDefaultPriority();
}
mode.addRule(pattern, eh, module, priority, true);
// if adding a rule to the omniMode (mode='all') add it to all
// the other modes as well
if (mode==omniMode) {
unnamedMode.addRule(pattern, eh, module, priority, false);
for (Mode m : modes.values()) {
m.addRule(pattern, eh, module, priority, false);
}
}
}
/**
* Get the template rule matching a given item whose import precedence
* is in a particular range. This is used to support the xsl:apply-imports function
* @param item The item to be matched
* @param mode The mode for which a rule is required
* @param min The minimum import precedence that the rule must have
* @param max The maximum import precedence that the rule must have
* @param c The Controller for the transformation
* @return The template rule to be invoked
* @throws XPathException if an error occurs matching a pattern
*/
public Rule getTemplateRule (Item item, Mode mode, int min, int max, XPathContext c)
throws XPathException {
if (mode==null) {
mode = unnamedMode;
}
return mode.getRule(item, min, max, c);
}
/**
* Get the next-match handler after the current one
* @param node The node to be matched
* @param mode The processing mode
* @param currentRule The current template rule
* @param c The dynamic context for the transformation
* @return The template rule to be executed
* @throws XPathException if an error occurs while matching a pattern
*/
public Rule getNextMatchHandler(Item node, Mode/*@Nullable*/ mode, Rule currentRule, XPathContext c)
throws XPathException {
if (mode==null) {
mode = unnamedMode;
}
return mode.getNextMatchRule(node, currentRule, c);
}
/**
* Allocate rankings to the rules within each mode. This method must be called when all
* the rules in each mode are known
* @throws XPathException if an error occurs
*/
public void computeRankings() throws XPathException {
unnamedMode.computeRankings();
for (Mode mode : modes.values()) {
mode.computeRankings();
}
}
/**
* Invert streamable templates in all streamable modes
* @param opt the optimizer (Always a Saxon-EE optimizer)
* @throws XPathException if the templates are not streamable
*/
public void invertStreamableTemplates(Optimizer opt) throws XPathException {
unnamedMode.invertStreamableTemplates(opt);
for (Mode mode : modes.values()) {
mode.invertStreamableTemplates(opt);
}
}
/**
* Explain (that is, output the expression tree) all template rules
* @param presenter the object used to present the output
*/
public void explainTemplateRules(ExpressionPresenter presenter) {
presenter.startElement("templateRules");
unnamedMode.explainTemplateRules(presenter);
for (Mode mode : modes.values()) {
int s = presenter.startElement("mode");
if (!mode.isDefaultMode()) {
presenter.emitAttribute("name", mode.getModeName().getDisplayName());
}
presenter.emitAttribute("streamable", Boolean.toString(mode.isStreamable()));
mode.explainTemplateRules(presenter);
int e = presenter.endElement();
if (s != e) {
throw new IllegalStateException("tree unbalanced");
}
}
presenter.endElement();
}
}