ElemTemplateElement.hpp

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/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the  "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
#if !defined(XALAN_ELEMTEMPLATEELEMENT_HEADER_GUARD)
#define XALAN_ELEMTEMPLATEELEMENT_HEADER_GUARD 



// Base include file.  Must be first.
#include <xalanc/XSLT/XSLTDefinitions.hpp>



#include <xalanc/XalanDOM/XalanDOMString.hpp>
#include <xalanc/XalanDOM/XalanNode.hpp>



#include <xalanc/PlatformSupport/DOMStringHelper.hpp>
#include <xalanc/PlatformSupport/PrefixResolver.hpp>
#include <xalanc/PlatformSupport/XalanLocator.hpp>



#include <xalanc/XPath/XalanQNameByReference.hpp>



#include <xalanc/XSLT/NamespacesHandler.hpp>



#include "LocalMsgIndex.hpp"



XALAN_DECLARE_XERCES_CLASS(AttributeList)
XALAN_DECLARE_XERCES_CLASS(Locator)



XALAN_CPP_NAMESPACE_BEGIN



typedef XERCES_CPP_NAMESPACE_QUALIFIER AttributeList    AttributeListType;
typedef XERCES_CPP_NAMESPACE_QUALIFIER Locator          LocatorType;


XALAN_USING_XERCES(AttributeList)
XALAN_USING_XERCES(Locator)
class ElemTemplate;
class ElemTextLiteral;
class NamespacesHandler;
class Stylesheet;
class StylesheetConstructionContext;
class StylesheetExecutionContext;
class XPath;



class XALAN_XSLT_EXPORT ElemTemplateElement : public PrefixResolver
{
     
public:

    /**
     * Construct a template element instance.
     * 
     * @param constructionContext  context when object constructed
     * @param stylesheetTree       owning stylesheet
     * @param lineNumber           line in the XSLT file where the element occurs
     * @param columnNumber         column index in the XSLT file where the
     *                             element occurs
     * @param xslToken             an integer representing the type of instance.
     */
    ElemTemplateElement(
            StylesheetConstructionContext&  constructionContext,
            Stylesheet&                     stylesheetTree,
            XalanFileLoc                    lineNumber,
            XalanFileLoc                    columnNumber,
            int                             xslToken);

    /**
     * Special constructor used by dummy elements which do not exist in the
     * final stylesheet.
     * 
     * @param constructionContext  context when object constructed
     * @param stylesheetTree       owning stylesheet
     * @param baseURI              The base URI of the XSLT file where the element occurs.
     * @param lineNumber           line in the XSLT file where the element occurs
     * @param columnNumber         column index in the XSLT file where the
     *                             element occurs
     * @param xslToken             an integer representing the type of instance.
     */
    ElemTemplateElement(
            StylesheetConstructionContext&  constructionContext,
            Stylesheet&                     stylesheetTree,
            int                             xslToken,
            const XalanDOMString&           baseURI = XalanDOMString(XalanMemMgrs::getDummyMemMgr()),
            XalanFileLoc                    lineNumber = XalanLocator::getUnknownValue(),
            XalanFileLoc                    columnNumber = XalanLocator::getUnknownValue());

    virtual
    ~ElemTemplateElement();

    /** 
     * Get the Locator for the node.  This may return 0.
     * 
     * @return The Locator for the node.
     */
    virtual const Locator*
    getLocator() const;

    /** 
     * See if this is a xmlns attribute or in a non-XSLT.
     * 
     * @param attrName qualified name of attribute
     * @param atts    attribute list where the element comes from (not used at 
     *                this time)
     * @param which   index into the attribute list (not used at this time)
     * @param constructionContext The current construction context
     * @return        true if this is a namespace name
     */
    virtual bool
    isAttrOK(
            const XalanDOMChar*             attrName,
            const AttributeListType&        atts,
            XalanSize_t                     which,
            StylesheetConstructionContext&  constructionContext) const;

    /** 
     * Tell whether or not this is a xml:space attribute and, if so, process it.
     * 
     * @param elementName  name of the element with the attribute
     * @param aname  name of the attribute in question
     * @param atts   attribute list that owns the attribute
     * @param which  index of the attribute into the attribute list
     * @param constructionContext The current construction context
     * @return       true if this is a xml:space attribute
     */
    bool
    processSpaceAttr(
            const XalanDOMChar*             elementName,
            const XalanDOMChar*             aname,
            const AttributeListType&        atts,
            XalanSize_t                     which,
            StylesheetConstructionContext&  constructionContext);

    /** 
     * Validate that the string is an NCName.
     * 
     * @param s name in question
     * @return  true if the string is a valid NCName according to XML rules
     * @see http://www.w3.org/TR/REC-xml-names#NT-NCName
     */
    static bool
    isValidNCName(const XalanDOMString&     s);

#if !defined(XALAN_RECURSIVE_STYLESHEET_EXECUTION)

    /**
     * Completes  "pre-processing" before any sub-elements are invoked 
     * (i.e. children, attribute sets and templates).   If there are 
     * no sub-elements it executes the primary function of the element.
     *
     * @param executionContext  context to execute this element
     */
    virtual const ElemTemplateElement*
    startElement(StylesheetExecutionContext&    executionContext) const;

    /**
     * Completes  "post-processing" afer any sub-elements are invoked 
     * (i.e. children, attribute sets and templates).   If there are 
     * no sub-elements it does nothing
     *
     * @param executionContext  context to execute this element
     */
    virtual void
    endElement(StylesheetExecutionContext&      executionContext) const;

    /**
     * Execute the element.
     *
     * @param execute   context to execute this element
     */
    virtual void
    execute(StylesheetExecutionContext&     executionContext) const;

    /** 
     * Execute the children of this element.
     * 
     * @param execute   context to execute this element
     */
    virtual void
    executeChildren(StylesheetExecutionContext&     executionContext) const;

    /**
     * Returns the element that invoked this element.
     * @returns element that invoked this element.
     */
    virtual const ElemTemplateElement*
    getInvoker(StylesheetExecutionContext&  executionContext) const;

#else

    /** 
     * Execute the element's primary function.  Subclasses of this function may
     * recursively execute down the element tree.
     * 
     * @param executionContext  The current execution context
     */
    virtual void
    execute(StylesheetExecutionContext&     executionContext) const;

    /** 
     * Process the children of a template.
     * 
     * @param processor  XSLT processor instance
     */
    virtual void
    executeChildren(StylesheetExecutionContext&     executionContext) const;

    /** 
     * Set the current node and process the children of a template.
     * 
     * @param processor  XSLT processor instance
     * @param sourceNode current node
     */
    virtual void
    executeChildren(
            StylesheetExecutionContext&     executionContext,
            XalanNode*                      sourceNode) const;

    /**
     * Take the contents of a template element, process it, and
     * convert it to a string.  Returns a const reference to
     * the resulting string value.  Note that this may _not_ be
     * the XalanDOMString instance passed in, if an optimization
     * is available to return a pre-existing string.
     * 
     * @param executionContext  The current execution context
     * @param result result of executing the elements children
     * @result a reference to a string containing the result.
     */
    const XalanDOMString&
    childrenToString(
            StylesheetExecutionContext&     executionContext,
            XalanDOMString&                 result) const;

    /**
     * Take the contents of a template element, process it, and
     * convert it to a string.  Then, add an attribute to the
     * result tree using the provided name and the string value.
     * 
     * @param executionContext  The current execution context
     * @param theName The name for the result attribute
     */
    void
    childrenToResultAttribute(
            StylesheetExecutionContext&     executionContext,
            const XalanDOMString&           theName) const;

    /**
     * Take the contents of a template element, process it, and
     * convert it to a string.  Then, add a comment to the
     * result tree using the string value.
     * 
     * @param executionContext  The current execution context
     */
    void
    childrenToResultComment(StylesheetExecutionContext& executionContext) const;

    /**
     * Take the contents of a template element, process it, and
     * convert it to a string.  Then, add a processing instruction
     * to the result tree using the string value, and the provided
     * target.
     * 
     * @param executionContext  The current execution context
     * @param theName The name for the result attribute
     */
    void
    childrenToResultPI(
            StylesheetExecutionContext&     executionContext,
            const XalanDOMString&           theTarget) const;

    /** 
     * Get an integer representation of the element type.
     * 
     * @return integer representation of the element, defined in the Constants
     *         class
     * @see class Constants
     */
#endif
    
    int
    getXSLToken() const
    {
        return m_xslToken;
    }

    /** 
     * Tell if the element will generate text which is XML whitespace.
     * 
     * @return true if the text is pure whitespace
     */
    virtual bool
    isWhitespace() const;

    /** 
     * Get a string for the name of the element.  Useful for debugging purposes,
     * and error reporting.
     * 
     * @return A string containing the name of the element.
     */
    virtual const XalanDOMString&
    getElementName() const = 0;

    /** 
     * Get the QName associated with any name attribute of this element.
     * If the element has no name attribute, this will be an empty QName.
     * 
     * @return A string containing the name of the element.
     */
    virtual const XalanQName&
    getNameAttribute() const;

    /** 
     * Called during compilation when an instance is not parented by
     * another element, and thus, is a child of the stylesheet..
     * 
     * @param constructionContext  The current construction context
     * @param theStylesheet The owning stylesheet
     * @return nothing
     */
    virtual void
    addToStylesheet(
            StylesheetConstructionContext&  constructionContext,
            Stylesheet&                     theStylesheet);

    /** 
     * Called during compilation to process xsl:sort elements in
     * the stylesheet.
     *
     * @param constructionContext  The current construction context
     * @param theStylesheet The owning stylesheet
     * @param atts The list of attributes for the sort element
     * @param locator A Locator instance for error reporting, if available.
     *
     * @return nothing
     */
    virtual void
    processSortElement(
            StylesheetConstructionContext&  constructionContext,
            Stylesheet&                     theStylesheet,
            const AttributeListType&        atts,
            const Locator*                  locator = 0);

    /**
     * Sets a flag indicating this is the default template
     *
     * @param value The value of flag.
     */
    virtual void
    setDefaultTemplate(bool     value);

    /** 
     * Get the namespaces handler for this element.
     * 
     * @return The element's NamespacesHandler instance.
     */
    const NamespacesHandler&
    getNamespacesHandler() const
    {
        return m_namespacesHandler;
    }

    /**
     * Retrieve the stylesheet from which this element comes
     * 
     * @return reference to source stylesheet
     */
    const Stylesheet&
    getStylesheet() const
    {
        return m_stylesheet;
    }

    /** 
     * Set the flag indicating construction of the element is completed.
     *
     * @param fValue  The value to set
     */
    void
    setFinishedConstruction(bool    fValue)
    {
        setFlag(eFinishedConstruction, fValue);
    }

    /** 
     * Get the flag indicating construction of the element is completed.
     */
    bool
    getFinishedConstruction() const
    {
        return getFlag(eFinishedConstruction);
    }

    /**
     * Called after construction is completed.
     */
    virtual void
    postConstruction(
            StylesheetConstructionContext&  constructionContext,
            const NamespacesHandler&        theParentHandler);

    // Type-safe getters/setters...

    /**
     * Get the first child.
     * 
     * @return first child node of this node
     */
    virtual ElemTemplateElement*
    getFirstChildElem() const;

#if !defined(XALAN_RECURSIVE_STYLESHEET_EXECUTION)
    /**
     * Method to initiate the execution of the element's children.
     *
     * @param executionContext  context to execute this element
     * @returns the first child element to execute
     */
    virtual const ElemTemplateElement*
    beginExecuteChildren(
            StylesheetExecutionContext& executionContext) const;


    /**
     * Method to indicate the execution of the element's children
     * is complete
     *
     * @param executionContext  context to execute this element
     */
    virtual void
    endExecuteChildren(
            StylesheetExecutionContext& executionContext) const;

    /**
     * Method to initiate output from the children
     * to a string.
     *
     * @param executionContext      context to execute this element
     * @param result                string to contain the final result
     * @returns                     the first child element to execute
     */
    const ElemTemplateElement*
    beginChildrenToString(
            StylesheetExecutionContext&     executionContext,
            XalanDOMString&                 result) const;

    
    /**
     * Method to indicate string output from the children is 
     * complete.
     *
     * @param executionContext      context to execute this element
     */
    void
    endChildrenToString(
            StylesheetExecutionContext&     executionContext) const;
#endif


    /**
     * Set the first child.
     *
     * theChild - the new value for the first child.
     *
     * @return nothing
     */
    virtual void
    setFirstChildElem(ElemTemplateElement*  theChild);

    /**
     * Get the last child.
     * 
     * @return last child node of this node
     */
    virtual ElemTemplateElement*
    getLastChildElem() const;

    /**
     * Get the next sibling.
     * 
     * @return next sibling node of this node
     */
    virtual ElemTemplateElement*
    getNextSiblingElem() const;

#if !defined(XALAN_RECURSIVE_STYLESHEET_EXECUTION)

    /**
     * Returns the next sub-element 
     *(i.e. children, attribute-sets, templates) to execute.
     *
     * @param executionContext      context to execute element
     * @param currentElem           the last sub-element to be executed
     * @returns                     next sub-element to execute,  0 only if no more sub-elements to execute
     */
    virtual const ElemTemplateElement*
    getNextChildElemToExecute(
            StylesheetExecutionContext& executionContext,
            const ElemTemplateElement*  currentElem) const;

    /**
     * Returns the first sub-element
     *(i.e. children, attribute-sets, templates) to execute.
     *
     * @param executionContext      context to execute element
     * @returns                     first sub-element to execute,  0 only if no sub-elements to execute
     */
    virtual const ElemTemplateElement*
    getFirstChildElemToExecute(
            StylesheetExecutionContext& executionContext) const;

    /**
     * Filters sub-elements that should be executed
     *
     * @param executionContext      context to execute element
     * @param element               the element to be executed
     * @returns                     true if element should be executed, false otherwise
     */
    virtual bool executeChildElement(
            StylesheetExecutionContext& executionContext,
            const ElemTemplateElement* element) const;
#endif

    /**
     * Set the next sibling.
     *
     * theSibling - the new value for the next sibling.
     *
     * @return nothing
     */
    virtual void
    setNextSiblingElem(ElemTemplateElement*     theSibling);

    /**
     * Get the previous sibling.
     * 
     * @return previous sibling node of this node
     */
    virtual ElemTemplateElement*
    getPreviousSiblingElem() const;

    /**
     * Set the previous sibling.
     *
     * theSibling - the new value for the previous sibling.
     *
     * @return nothing
     */
    virtual void
    setPreviousSiblingElem(ElemTemplateElement*     theSibling);

    /**
     * Get the parent node.
     * 
     * @return parent node of this node
     */
    virtual ElemTemplateElement*
    getParentNodeElem() const;

    /**
     * Set the parent node.
     *
     * theParent - the new value for the parent.
     *
     * @return nothing
     */
    virtual void
    setParentNodeElem(ElemTemplateElement*      theParent);

    /**
     * Append a child.
     *
     * theParent - the new value for the parent.
     *
     * @return nothing
     */
    virtual ElemTemplateElement*
    appendChildElem(ElemTemplateElement*    newChild);

    /**
     * Get XPath pattern/expression of one of the element atribute
     *
     * @index   number of the attribute. If an attribute has more
     *              then one attribute with pattern/expression,the order of 
     *              the returned expressions are undefined
     *
     * @return pointer or null 
     */
    virtual const XPath*
    getXPath(XalanSize_t    index) const;

    // These interfaces are inherited from PrefixResolver...

    virtual const XalanDOMString*
    getNamespaceForPrefix(const XalanDOMString& prefix) const;

    virtual const XalanDOMString&
    getURI() const;

    // A class that implements the XalanLocator
    // abstract base class.  ElemTemplateElement
    // uses this class to provide locator information.
    class LocatorProxy : public XalanLocator
    {
    public:

        LocatorProxy(
                    XalanFileLoc            theLineNumber,
                    XalanFileLoc            theColumnNumber,
                    const XalanDOMString&   theURI);

        virtual
        ~LocatorProxy();

        virtual const XMLCh*
        getPublicId() const;

        virtual const XMLCh*
        getSystemId() const;

        virtual XalanFileLoc
        getLineNumber() const;

        virtual XalanFileLoc
        getColumnNumber() const;

        const XalanDOMString&
        getURI() const
        {
            return m_uri;
        }

    private:

        // Not implemented...
        LocatorProxy(const LocatorProxy&);

        LocatorProxy&
        operator=(const LocatorProxy&);

        bool
        operator==(const LocatorProxy&) const;

        // data members...
        const XalanFileLoc      m_lineNumber;

        const XalanFileLoc      m_columnNumber;

        const XalanDOMString&   m_uri;
    };


    XalanFileLoc
    getLineNumber() const
    {
        return m_locatorProxy.getLineNumber();
    }

    XalanFileLoc
    getColumnNumber() const
    {
        return m_locatorProxy.getColumnNumber();
    }

    bool
    hasParams() const
    {
        return getFlag(eHasParams);
    }

    bool
    hasVariables() const
    {
        return getFlag(eHasVariables);
    }

    bool
    hasSingleTextChild() const
    {
        return getFlag(eHasSingleTextChild);
    }

    bool
    hasChildren() const
    {
        return m_firstChild != 0 ? true : false;
    }

    bool
    hasDirectTemplate() const
    {
        return getFlag(eHasDirectTemplate);
    }

    bool
    canGenerateAttributes() const
    {
        return getFlag(eCanGenerateAttributes);
    }

    bool
    isDefaultTemplate() const
    {
        return getFlag(eDefaultTemplate);
    }

protected:

    void
    canGenerateAttributes(bool  value)
    {
        setFlag(eCanGenerateAttributes, value);
    }

    void
    hasPrefix(bool  value)
    {
        setFlag(eHasPrefix, value);
    }

    bool
    hasPrefix() const
    {
        return getFlag(eHasPrefix);
    }

    void
    preserveSpace(bool  value)
    {
        setFlag(eSpacePreserve, value);
    }

    bool
    preserveSpace() const
    {
        return getFlag(eSpacePreserve);
    }

    void
    disableOutputEscaping(bool  value)
    {
        setFlag(eDisableOutputEscaping, value);
    }

    bool
    disableOutputEscaping() const
    {
        return getFlag(eDisableOutputEscaping);
    }

    /**
     * Process the exclude-result-prefixes or the extension-element-prefixes
     * attributes, for the purpose of prefix exclusion.
     *
     * @param constructionContext  context when object consructed
     * @param stylesheetTree The current Stylesheet object.
     * @param localName The local name of the attribute.
     * @param attrValue The value of the attribute.
     */
    bool
    processPrefixControl(
            StylesheetConstructionContext&  constructionContext,
            const Stylesheet&               stylesheetTree,
            const XalanDOMString&           localName,
            const XalanDOMChar*             attrValue);

    /**
     * Get the namespace for a given prefix.
     * 
     * @param prefix The prefix to search for
     * @param fExists If not null, set to true if the namespace was defined.
     * @return The namespace string.
     */
    const XalanDOMString*
    getNamespaceForPrefixInternal(const XalanDOMString&     prefix) const;

#if !defined(XALAN_RECURSIVE_STYLESHEET_EXECUTION)
    /**
     * Given an element, find the corresponding
     * template.
     * 
     * @param executionContext  The current execution context
     * @param xslInstruction    The calling element
     * @param template          The template to use if xsl:for-each, or null.
     * @param child             The source context node.
     * @returns                 matching template if any.  Returns 0 if no matching template or corresponds to a default rule.
     */
    virtual const ElemTemplateElement*
    findTemplateToTransformChild(
            StylesheetExecutionContext&     executionContext,
            const ElemTemplateElement&      xslInstruction,
            const ElemTemplateElement*      theTemplate,
            XalanNode*                      child) const;

    /**
     * Given an element, find the corresponding
     * template.
     * 
     * @param executionContext  The current execution context
     * @param xslInstruction    The calling element
     * @param template          The template to use if xsl:for-each, or null.
     * @param child             The source context node.
     * @param nodeType The type of child.
     * @returns                 matching template if any.  Returns 0 if no matching template or corresponds to a default rule.
     */
    virtual const ElemTemplateElement*
    findTemplateToTransformChild(
            StylesheetExecutionContext&     executionContext,
            const ElemTemplateElement&      xslInstruction,
            const ElemTemplateElement*      theTemplate,
            XalanNode*                      child,
            XalanNode::NodeType             nodeType) const;
#else
    /**
     * Given an element, find the corresponding
     * template and process the contents.
     * 
     * @param executionContext The current execution context
     * @param xslInstruction The calling element
     * @param template The template to use if xsl:for-each, or null.
     * @param child The source context node.
     */
    virtual void
    transformChild(
            StylesheetExecutionContext&     executionContext,
            const ElemTemplateElement&      xslInstruction,
            const ElemTemplateElement*      theTemplate,
            XalanNode*                      child) const;

    /**
     * Given an element, find the corresponding
     * template and process the contents.
     * 
     * @param executionContext The current execution context
     * @param xslInstruction The calling element
     * @param template The template to use if xsl:for-each, or null.
     * @param child The source context node.
     * @param nodeType The type of child.
     */
    virtual void
    transformChild(
            StylesheetExecutionContext&     executionContext,
            const ElemTemplateElement&      xslInstruction,
            const ElemTemplateElement*      theTemplate,
            XalanNode*                      child,
            XalanNode::NodeType             nodeType) const;
#endif
    
    /**
     * Given an xsl token type, determine whether or not a child
     * of that type is allowed.  This is so derived types can
     * determine whether a particular type of child is allowed for
     * the instance.  It is called from appendChildElem().
     *
     * The default is to allow no types (no children)
     *
     * @param xslToken The xsl token value of the child.
     *
     * @return true if the child is allowed, or false if not.
     */
    virtual bool
    childTypeAllowed(int    xslToken) const;

    /**
     * Called after construction is completed.  This is a hook for
     * deriving classes to handle post-construction with the
     * instances HamespaceHandler instance, which is otherwise only
     * available through a const accessor.
     */
    virtual void
    namespacesPostConstruction(
            StylesheetConstructionContext&  constructionContext,
            const NamespacesHandler&        theParentHandler,
            NamespacesHandler&              theHandler);

    const NamespacesHandler&
    getNamespaces() const
    {
        return m_namespacesHandler;
    }

    /**
     * A convenience function for loading a message
     * and reporting an error through the provided
     * StylesheetExecutionContext instance.
     *
     * @param theContext The StylesheetExecutionContext to use
     * @param theCode The code of the message
     */
    void
    error(
            StylesheetExecutionContext&     theContext,
            XalanMessages::Codes            theCode) const;

    /**
     * A convenience function for loading a message
     * and reporting an error through the provided
     * StylesheetExecutionContext instance.
     *
     * @param theContext The StylesheetExecutionContext to use
     * @param theCode The code of the message
     * @param theToken The substitution token for the message
     */
    void
    error(
            StylesheetExecutionContext&     theContext,
            XalanMessages::Codes            theCode,
            const XalanDOMString&           theToken) const;

    /**
     * A convenience function for loading a message
     * and reporting an error through the provided
     * StylesheetExecutionContext instance.
     *
     * @param theContext The StylesheetExecutionContext to use
     * @param theCode The code of the message
     * @param theLocator The Locator instance to use, if any
     */
    void
    error(
            StylesheetExecutionContext&     theContext,
            XalanMessages::Codes            theCode,
            const Locator*                  theLocator) const;

    /**
     * A convenience function for loading a message
     * and reporting a warning through the provided
     * StylesheetExecutionContext instance.
     *
     * @param theContext The StylesheetExecutionContext to use
     * @param theCode The code of the message
     */
    void
    warn(
            StylesheetExecutionContext&     theContext,
            XalanMessages::Codes            theCode) const;

    /**
     * A convenience function for loading a message
     * and reporting a warning through the provided
     * StylesheetExecutionContext instance.
     *
     * @param theContext The StylesheetExecutionContext to use
     * @param theCode The code of the message
     * @param theToken The substitution token for the message
     */
    void
    warn(
            StylesheetExecutionContext&     theContext,
            XalanMessages::Codes            theCode,
            const XalanDOMString&           theToken) const;

    /**
     * A convenience function for loading a message
     * and reporting a warning through the provided
     * StylesheetExecutionContext instance.
     *
     * @param theContext The StylesheetExecutionContext to use
     * @param theCode The code of the message
     * @param theLocator The Locator instance to use, if any
     */
    void
    warn(
            StylesheetExecutionContext&     theContext,
            XalanMessages::Codes            theCode,
            const Locator*                  theLocator) const;

    /**
     * A convenience function for loading a message
     * and reporting an error through the provided
     * StylesheetConstructionContext instance.
     *
     * @param theContext The StylesheetConstructionContext to use
     * @param theCode The code of the message
     */
    void
    error(
            StylesheetConstructionContext&  theContext,
            XalanMessages::Codes            theCode);

    /**
     * A convenience function for loading a message
     * and reporting an error through the provided
     * StylesheetConstructionContext instance.
     *
     * @param theContext The StylesheetConstructionContext to use
     * @param theCode The code of the message
     * @param theToken The substitution token for the message
     * @param theLocator The Locator instance to use, if any
     */
    void
    error(
            StylesheetConstructionContext&  theContext,
            XalanMessages::Codes            theCode,
            const XalanDOMString&           theToken);

    /**
     * A convenience function for loading a message
     * and reporting an error through the provided
     * StylesheetConstructionContext instance.
     *
     * @param theContext The StylesheetConstructionContext to use
     * @param theCode The code of the message
     * @param theToken The substitution token for the message
     * @param theLocator The Locator instance to use, if any
     */
    void
    error(
            StylesheetConstructionContext&  theContext,
            XalanMessages::Codes            theCode,
            const XalanDOMString&           theToken,
            const Locator*                  theLocator);

    /**
     * A convenience function for loading a message
     * and reporting an error through the provided
     * StylesheetConstructionContext instance.
     *
     * @param theContext The StylesheetConstructionContext to use
     * @param theCode The code of the message
     * @param theToken1 The first substitution token for the message
     * @param theToken2 The second substitution token for the message
     */
    void
    error(
            StylesheetConstructionContext&  theContext,
            XalanMessages::Codes            theCode,
            const XalanDOMString&           theToken1,
            const XalanDOMString&           theToken2);

    /**
     * A convenience function for loading a message
     * and reporting an error through the provided
     * StylesheetConstructionContext instance.
     *
     * @param theContext The StylesheetConstructionContext to use
     * @param theCode The code of the message
     * @param theToken1 The first substitution token for the message
     * @param theToken2 The second substitution token for the message
     */
    void
    error(
            StylesheetConstructionContext&  theContext,
            XalanMessages::Codes            theCode,
            const XalanDOMChar*             theToken1,
            const XalanDOMChar*             theToken2);

    /**
     * A convenience function for loading a message
     * and reporting an error through the provided
     * StylesheetConstructionContext instance.
     *
     * @param theContext The StylesheetConstructionContext to use
     * @param theCode The code of the message
     * @param theToken1 The first substitution token for the message
     * @param theToken2 The second substitution token for the message
     * @param theToken3 The third substitution token for the message
     */
    void
    error(
            StylesheetConstructionContext&  theContext,
            XalanMessages::Codes            theCode,
            const XalanDOMChar*             theToken1,
            const XalanDOMChar*             theToken2,
            const XalanDOMChar*             theToken3);

    /**
     * A convenience function for loading a message
     * and reporting a warning through the provided
     * StylesheetConstructionContext instance.
     *
     * @param theContext The StylesheetConstructionContext to use
     * @param theCode The code of the message
     * @param theToken1 The first substitution token for the message
     * @param theToken2 The second substitution token for the message
     * @param theToken3 The third substitution token for the message
     */
    void
    warn(
            StylesheetConstructionContext&  theContext,
            XalanMessages::Codes            theCode,
            const XalanDOMChar*             theToken1,
            const XalanDOMChar*             theToken2,
            const XalanDOMChar*             theToken3);

    // A handy empty XalanDOMString instance for
    // derived classes to use.
    static const XalanDOMString     s_emptyString;

private:

    enum eFlags
    { 
        eHasParams = 1,
        eHasSingleTextChild = 2,
        eHasVariables = 4,
        eHasDirectTemplate = 8,
        eCanGenerateAttributes = 16,
        eDefaultTemplate = 32,
        eSpacePreserve = 64,
        eFinishedConstruction = 128,
        eHasPrefix = 256,
        eDisableOutputEscaping = 512
    };

    bool
    getFlag(eFlags  theFlag) const
    {
        return m_flags & theFlag ? true : false;
    }

    void
    setFlag(
            eFlags  theFlag,
            bool    theValue)
    {
        if (theValue == true)
        {
            m_flags |= theFlag;
        }
        else
        {
            m_flags &= ~theFlag;
        }
    }


#if defined(XALAN_RECURSIVE_STYLESHEET_EXECUTION)
    /** 
     * Take the contents of a template element, process it, and
     * convert it to a string.
     * 
     * @param executionContext  The current execution context
     * @param result result of executing the elements children
     * @result a reference to a string containing the result.
     */
    XalanDOMString&
    doChildrenToString(
            StylesheetExecutionContext&     executionContext, 
            XalanDOMString&                 result) const;
#endif

    Stylesheet&             m_stylesheet;

    /*
     * This object handles all result tree namespace processing.
     */
    NamespacesHandler       m_namespacesHandler;

    const int               m_xslToken;

    ElemTemplateElement*    m_parentNode;
    ElemTemplateElement*    m_nextSibling;
    ElemTemplateElement*    m_previousSibling;

    union
    {
        ElemTemplateElement*    m_firstChild;
        const ElemTemplate*     m_directTemplate;
        const ElemTextLiteral*  m_textLiteralChild;
    };

    LocatorProxy            m_locatorProxy;

    unsigned short          m_flags;

    static const XalanQNameByReference      s_emptyQName;

    // Not implemented...
    ElemTemplateElement(const ElemTemplateElement&);

    ElemTemplateElement&
    operator=(const ElemTemplateElement&);

    bool
    operator==(const ElemTemplateElement&) const;
};



XALAN_CPP_NAMESPACE_END



#endif  // XALAN_ELEMTEMPLATEELEMENT_HEADER_GUARD