src/xalanc/XPath/XPathFunctionTable.hpp

/*
 * 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(XPATHFUNCTIONTABLE_HEADER_GUARD_1357924680)
#define XPATHFUNCTIONTABLE_HEADER_GUARD_1357924680



// Base include file.  Must be first.
#include <xalanc/XPath/XPathDefinitions.hpp>



#include <algorithm>



#include <xalanc/XalanDOM/XalanDOMString.hpp>



#include <xalanc/Include/STLHelper.hpp>



#include <xalanc/XPath/Function.hpp>
#include <xalanc/XPath/XalanXPathException.hpp>



namespace XALAN_CPP_NAMESPACE {



/**
 * Exception class thrown when an unknown function is encountered
 */
class XALAN_XPATH_EXPORT XPathExceptionFunctionNotAvailable : public XalanXPathException
{
public:

    typedef Function::LocatorType   LocatorType;

    XPathExceptionFunctionNotAvailable(
            const XalanDOMString&   theFunctionName,
            XalanDOMString&         theResult,
            const Locator*          theLocator);

    XPathExceptionFunctionNotAvailable(const XPathExceptionFunctionNotAvailable& other);

    ~XPathExceptionFunctionNotAvailable();
};



/**
 * Exception class thrown when an installFunction() is called with a 
 * function name that is not supported.
 */
class XALAN_XPATH_EXPORT XPathExceptionFunctionNotSupported : public XalanXPathException
{
public:

    XPathExceptionFunctionNotSupported(
            const XalanDOMChar*     theFunctionName,
            XalanDOMString&         theResult,
            const Locator*          theLocator);

    XPathExceptionFunctionNotSupported(const XPathExceptionFunctionNotSupported& other);

    ~XPathExceptionFunctionNotSupported();
};



/**
 * Class defines a table of functions that can be called in XPath expresions.
 */
class XALAN_XPATH_EXPORT XPathFunctionTable
{
public:

    enum { InvalidFunctionNumberID = -1, TableSize = 36 };

    typedef size_t                      SizeType;
    typedef XalanDOMString::size_type   StringSizeType;
    typedef DeleteFunctor<Function>     DeleteFunctorType;

    /**
     * Constructor.
     *
     * @param fCreateTable If true, the internal table will be created.  Otherwise, CreateTable() must be called.
     */
    XPathFunctionTable(bool     fCreateTable = true);

    ~XPathFunctionTable();

    void
    setMemoryManager(MemoryManager& theManager)
    {
        m_memoryManager = &theManager;
    }
    /**
     * Set up the internal table.
     */
    void
    CreateTable();

    /**
     * Destroy the internal table.
     */
    void
    DestroyTable();

    /**
     * Retrieve the function object for a specified function name.  If
     * the named Function is not found, an exception is thrown.
     * 
     * @param theFunctionName The name of function
     * @param theLocator The Locator instance to use when reporting an error.
     * @return function named
     */
    const Function&
    get(
            const XalanDOMString&   theFunctionName,
            const Locator*          theLocator) const
    {
        const int   theFunctionID =
            getFunctionIndex(theFunctionName);

        if (theFunctionID != InvalidFunctionNumberID)
        {
            return *m_functionTable[theFunctionID];
        }
        else
        {
            MemoryManager* const    theManager = m_memoryManager;

            XalanDOMString   theResult(*theManager);

            throw XPathExceptionFunctionNotAvailable(
                    theFunctionName,
                    theResult,
                    theLocator);
        }
    }

private:

    /**
     * Retrieve the function object for a specified function name.
     *
     * @deprecated This operator is deprecated.
     * @param theFunctionName name of function
     * @return function named
     */
    const Function&
    operator[](const XalanDOMString&    theFunctionName) const
    {
        const int   theFunctionID =
            getFunctionIndex(theFunctionName);

        if (theFunctionID != InvalidFunctionNumberID)
        {
            return *m_functionTable[theFunctionID];
        }
        else
        {
            MemoryManager* const    theManager = m_memoryManager;

            XalanDOMString   theResult(*theManager);

            throw XPathExceptionFunctionNotAvailable(
                    theFunctionName,
                    theResult,
                    0);
        }
    }

public:

    /**
     * Retrieve the function object for a specified function ID number.
     * 
     * @param theFunctionID ID number of the function
     * @return function named
     */
    const Function&
    operator[](int  theFunctionID) const
    {
        assert(theFunctionID >= 0 && theFunctionID < TableSize);
        assert(m_functionTable[theFunctionID] != 0);

        return *m_functionTable[theFunctionID];
    }

    /**
     * Map a function ID to the corresponding name.
     * 
     * @param theFunctionID The ID number of the function
     * @return The name of the function, or an empty string if the function doesn't exist.
     */
    const XalanDOMString&
    idToName(int    theFunctionID,
                XalanDOMString& theResult) const
    {

        if (theFunctionID >= 0 && theFunctionID < TableSize)
        {
            theResult.assign(
                s_functionNames[theFunctionID].m_name,
                s_functionNames[theFunctionID].m_size);
        }

        return theResult;
    }

    /**
     * Map a function name to the corresponding ID number.
     * 
     * @param theName name of function
     * @return The ID number of function, or InvalidFunctionNumberID if the function doesn't exist.
     */
    int
    nameToID(const XalanDOMString&  theName) const
    {
        return getFunctionIndex(theName);
    }

    /**
     * Insert a named function into the function table.
     * 
     * @param theFunctionName name of function
     * @param theFunction     function object corresponding to name
     */
    void
    InstallFunction(
            const XalanDOMString&   theFunctionName,
            const Function&         theFunction)
    {
        InstallFunction(theFunctionName.c_str(), theFunction);
    }

    /**
     * Remove a named function from the function table.
     * 
     * @param theFunctionName name of function
     * @return true if the function was found and removed.
     */
    bool
    UninstallFunction(const XalanDOMString&     theFunctionName)
    {
        return UninstallFunction(theFunctionName.c_str());
    }

    /**
     * Insert a named function into the function table.
     * 
     * @param theFunctionName name of function
     * @param theFunction     function object corresponding to name
     */
    void
    InstallFunction(
            const XalanDOMChar*     theFunctionName,
            const Function&         theFunction);

    /**
     * Remove a named function from the function table.
     * 
     * @param theFunctionName name of function
     * @return true if the function was found and removed.
     */
    bool
    UninstallFunction(const XalanDOMChar*   theFunctionName);

    /**
     * Whether a named function is in the function table.
     * 
     * @param theFunctionName name of function
     * @return true if function is in table
     */
    bool
    isInstalledFunction(const XalanDOMString&   theFunctionName) const
    {
        return getFunctionIndex(theFunctionName) != InvalidFunctionNumberID ? true : false;
    }

    /**
     * Add a list of the names of installed functions to a vector of names.
     * 
     * @param theIterator function table iterator to append names to
     */
    template<class OutputIteratorType>
    void
    getInstalledFunctionNames(OutputIteratorType    theIterator) const
    {
        XalanDOMString  theString(XalanMemMgrs::getDefaultXercesMemMgr());

        for (int i = 0; i < TableSize; ++i)
        {
            if (m_functionTable[i] != 0)
            {
                theString.assign(
                    s_functionNames[i].m_name,
                    s_functionNames[i].m_size);

                *theIterator = theString;

                ++theIterator;
            }
        }
    }

    struct FunctionNameTableEntry
    {
        const XalanDOMChar*     m_name;

        StringSizeType          m_size;
    };

    // These are static strings for the functions supported.
    // Note that the XSLT functions are also here, since it's
    // just easier to do it this way.

    // The string "id"
    static const XalanDOMChar   s_id[];

    // The string "key"
    static const XalanDOMChar   s_key[];

    // The string "not"
    static const XalanDOMChar   s_not[];

    // The string "sum"
    static const XalanDOMChar   s_sum[];

    // The string "lang"
    static const XalanDOMChar   s_lang[];

    // The string "last"
    static const XalanDOMChar   s_last[];

    // The string "name"
    static const XalanDOMChar   s_name[];

    // The string "true"
    static const XalanDOMChar   s_true[];

    // The string "count"
    static const XalanDOMChar   s_count[];

    // The string "false"
    static const XalanDOMChar   s_false[];

    // The string "floor"
    static const XalanDOMChar   s_floor[];

    // The string "round"
    static const XalanDOMChar   s_round[];

    // The string "concat"
    static const XalanDOMChar   s_concat[];

    // The string "number"
    static const XalanDOMChar   s_number[];

    // The string "string"
    static const XalanDOMChar   s_string[];

    // The string "boolean"
    static const XalanDOMChar   s_boolean[];

    // The string "ceiling"
    static const XalanDOMChar   s_ceiling[];

    // The string "current"
    static const XalanDOMChar   s_current[];

    // The string "contains"
    static const XalanDOMChar   s_contains[];

    // The string "document"
    static const XalanDOMChar   s_document[];

    // The string "position"
    static const XalanDOMChar   s_position[];

    // The string "substring"
    static const XalanDOMChar   s_substring[];

    // The string "translate"
    static const XalanDOMChar   s_translate[];

    // The string "local-name"
    static const XalanDOMChar   s_localName[];

    // The string "generate-id"
    static const XalanDOMChar   s_generateId[];

    // The string "starts-with"
    static const XalanDOMChar   s_startsWith[];

    // The string "format-number"
    static const XalanDOMChar   s_formatNumber[];

    // The string "namespace-uri"
    static const XalanDOMChar   s_namespaceUri[];

    // The string "string-length"
    static const XalanDOMChar   s_stringLength[];

    // The string "normalize-space"
    static const XalanDOMChar   s_normalizeSpace[];

    // The string "substring-after"
    static const XalanDOMChar   s_substringAfter[];

    // The string "system-property"
    static const XalanDOMChar   s_systemProperty[];

    // The string "substring-before"
    static const XalanDOMChar   s_substringBefore[];

    // The string "element-available"
    static const XalanDOMChar   s_elementAvailable[];

    // The string "function-available"
    static const XalanDOMChar   s_functionAvailable[];

    // The string "unparsed-entity-uri"
    static const XalanDOMChar   s_unparsedEntityUri[];

    // A table of function names.
    static const FunctionNameTableEntry         s_functionNames[];

    // The size of the table.
    static const SizeType                       s_functionNamesSize;

private:

    static int
    getFunctionIndex(const XalanDOMString&  theName)
    {
        return getFunctionIndex(
                theName.c_str(),
                theName.length());
    }

    static int
    getFunctionIndex(const XalanDOMChar*    theName)
    {
        return getFunctionIndex(
                theName,
                XalanDOMString::length(theName));
    }

    static int
    getFunctionIndex(
            const XalanDOMChar*     theName,
            StringSizeType          theNameLength);

    MemoryManager*              m_memoryManager;

    const Function*             m_functionTable[TableSize];

    const Function** const      m_functionTableEnd;

    // The last one in the table of function names.
    static const FunctionNameTableEntry* const  s_lastFunctionName;
};



}



#endif  // XPATHFUNCTIONTABLE_HEADER_GUARD_1357924680