C++ AutoPtr::isWritable方法代码示例

//.........这里部分代码省略.........
                                                                            "also affected by the is-uris option."),
                                                      QVariant::String);
    focus.setMinimumOccurrence(0);
    focus.setNameless(true);
    parser.addArgument(focus);

    QApplicationArgument output(QLatin1String("output"),
                                QXmlPatternistCLI::tr("A local file to which the output should be written. "
                                                      "The file is overwritten, or if not exist, created. "
                                                      "If absent, stdout is used."),
                                qMetaTypeId<QIODevice *>());
    parser.addArgument(output);

    if(!parser.parse())
        return parser.exitCode();

    /* Get the query URI. */
    const QUrl effectiveURI(finalizeURI(parser, isURI, queryURI));

    QXmlQuery::QueryLanguage lang;

    if(effectiveURI.toString().endsWith(QLatin1String(".xsl")))
         lang = QXmlQuery::XSLT20;
    else
         lang = QXmlQuery::XQuery10;

    if(lang == QXmlQuery::XQuery10 && parser.has(initialTemplateName))
    {
        parser.message(QXmlPatternistCLI::tr("An initial template name cannot be specified when running an XQuery."));
        return QApplicationArgumentParser::ParseError;
    }

    QXmlQuery query(lang, namePool);

    query.setInitialTemplateName(qvariant_cast<QXmlName>(parser.value(initialTemplateName)));

    /* Bind external variables. */
    {
        const QVariantList parameters(parser.values(param));
        const int len = parameters.count();

        /* For tracking duplicates. */
        QSet<QString> usedParameters;

        for(int i = 0; i < len; ++i)
        {
            const Parameter p(qvariant_cast<Parameter>(parameters.at(i)));

            if(usedParameters.contains(p.first))
            {
                parser.message(QXmlPatternistCLI::tr("Each parameter must be unique, %1 is specified at least twice.").arg(p.first));
                return QApplicationArgumentParser::ParseError;
            }
            else
            {
                usedParameters.insert(p.first);
                query.bindVariable(p.first, QXmlItem(p.second));
            }
        }
    }

    if(parser.has(focus))
    {
        if(!query.setFocus(finalizeURI(parser, isURI, focus)))
            return QueryFailure;
    }
    else if(lang == QXmlQuery::XSLT20 && !parser.has(initialTemplateName))
    {
        parser.message(QXmlPatternistCLI::tr("When a stylesheet is used, a "
                                             "document must be specified as a focus, or an "
                                             "initial template name must be specified, or both."));
        return QApplicationArgumentParser::ParseError;
    }

    query.setQuery(effectiveURI);

    const QPatternist::AutoPtr<QIODevice> outDevice(qvariant_cast<QIODevice *>(parser.value(output)));
    Q_ASSERT(outDevice);
    Q_ASSERT(outDevice->isWritable());

    if(query.isValid())
    {
        typedef QPatternist::AutoPtr<QAbstractXmlReceiver> RecPtr;
        RecPtr receiver;

        if(parser.has(noformat))
            receiver = RecPtr(new QXmlSerializer(query, outDevice.data()));
        else
            receiver = RecPtr(new QXmlFormatter(query, outDevice.data()));

        const bool success = query.evaluateTo(receiver.data());

        if(success)
            return parser.exitCode();
        else
            return QueryFailure;
    }
    else
        return QueryFailure;
}