source: trunk/src/xmlpatterns/utils/qnamepool_p.h@ 594

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//
//  W A R N I N G
//  -------------
//
// This file is not part of the Qt API.  It exists purely as an
// implementation detail.  This header file may change from version to
// version without notice, or even be removed.
//
// We mean it.

#ifndef Patternist_NamePool_H
#define Patternist_NamePool_H

#include <QHash>
#include <QReadLocker>
#include <QReadWriteLock>
#include <QSharedData>
#include <QString>
#include <QVector>
#include <QXmlName>

#include <QtXmlPatterns/private/qprimitives_p.h>

QT_BEGIN_HEADER

QT_BEGIN_NAMESPACE

namespace QPatternist
{
    /**
     * @short Store names such as namespace bindings and QNames and allows them to
     * be referenced in efficient ways.
     *
     * Once a string have been inserted it stays there and cannot be removed. The
     * only way to deallocate any string in the NamePool is to deallocate the
     * NamePool itself, as a whole.
     *
     * This class is not only reentrant, it is thread-safe in all sense of the
     * word. All functions of this class can be called concurrently. This is
     * achieved by internal locking.
     *
     * @author Frans Englich <[email protected]>
     * @todo Use QSubStrings, we can save very many heap allocations by that.
     * @todo Check limits
     */
    class Q_AUTOTEST_EXPORT NamePool : public QSharedData
    {
    public:
        typedef QExplicitlySharedDataPointer<NamePool> Ptr;

    private:
        friend class StandardNamespaces;

        enum
        {
            NoSuchValue         = -1,
            /**
             * This must be identical to the amount of members in
             * StandardNamespaces.
             */
            StandardNamespaceCount = 11,
            StandardPrefixCount = 9,
            StandardLocalNameCount = 141
        };

        QVector<QString> m_prefixes;
        QVector<QString> m_namespaces;
        QVector<QString> m_localNames;

        /**
         * This hash contains no essential data, but speeds up
         * finding a prefix in m_prefixes by mapping a prefix(the key) to
         * the index into m_prefixes(which the value is).
         *
         * In other words, one can skip this variable at the cost of having
         * to linearly loop over prefixes, in order to find the entry.
         */
        QHash<QString, QXmlName::PrefixCode> m_prefixMapping;

        /**
         * Same as m_prefixMapping but applies for URIs, and hence m_namespaces instead
         * of m_prefixes.
         */
        QHash<QString, QXmlName::NamespaceCode> m_namespaceMapping;

        QHash<QString, QXmlName::LocalNameCode> m_localNameMapping;

        enum DefaultCapacities
        {