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#include <QtDebug>
#include "qxmlformatter.h"
#include "qxpathhelper_p.h"
#include "qxmlserializer_p.h"
QT_BEGIN_NAMESPACE
using namespace QPatternist;
class QXmlFormatterPrivate : public QXmlSerializerPrivate
{
public:
inline QXmlFormatterPrivate(const QXmlQuery &q,
QIODevice *const outputDevice);
int indentationDepth;
int currentDepth;
QString characterBuffer;
QString indentString;
/**
* Whether we /have/ sent nodes like processing instructions and comments
* to QXmlSerializer.
*/
QStack<bool> canIndent;
};
QXmlFormatterPrivate::QXmlFormatterPrivate(const QXmlQuery &query,
QIODevice *const outputDevice) : QXmlSerializerPrivate(query, outputDevice)
, indentationDepth(4)
, currentDepth(0)
{
indentString.reserve(30);
indentString.resize(1);
indentString[0] = QLatin1Char('\n');
canIndent.push(false);
}
/*!
\class QXmlFormatter
\brief The QXmlFormatter class is an implementation of QXmlSerializer for transforming XQuery output into formatted XML.
\reentrant
\since 4.4
\ingroup xml-tools
QXmlFormatter is a subclass of QXmlSerializer that formats the XML
output to make it easier for humans to read.
QXmlSerializer outputs XML without adding unnecessary whitespace.
In particular, it does not add \e {newlines} and indentation.
To make the XML output easier to read, QXmlFormatter adds \e{newlines}
and indentation by adding, removing, and modifying
\l{XQuery Sequence}{sequence nodes} that only consist of whitespace.
It also modifies whitespace in other places where it is not
significant; e.g., between attributes and in the document prologue.
For example, where the base class QXmlSerializer would
output this:
\quotefile doc/src/snippets/patternist/notIndented.xml
QXmlFormatter outputs this:
\quotefile doc/src/snippets/patternist/indented.xml
If you just want to serialize your XML in a human-readable
format, use QXmlFormatter as it is. The default indentation
level is 4 spaces, but you can set your own indentation value
setIndentationDepth().
The \e{newlines} and indentation added by QXmlFormatter are
suitable for common formats, such as XHTML, SVG, or Docbook,
where whitespace is not significant. However, if your XML will
be used as input where whitespace is significant, then you must
write your own subclass of QXmlSerializer or QAbstractXmlReceiver.
Note that using QXmlFormatter instead of QXmlSerializer will
increase computational overhead and document storage size due
to the insertion of whitespace.
Note also that the indentation style used by QXmlFormatter
remains loosely defined and may change in future versions of
Qt. If a specific indentation style is required then either
use the base class QXmlSerializer directly, or write your own
subclass of QXmlSerializer or QAbstractXmlReceiver.
Alternatively, you can subclass QXmlFormatter and reimplement
the callbacks there.
\snippet doc/src/snippets/code/src_xmlpatterns_api_qxmlformatter.cpp 0
*/
/*!
Constructs a formatter that uses the name pool and message
handler in \a query, and writes the result to \a outputDevice
as formatted XML.
\a outputDevice is passed directly to QXmlSerializer's constructor.
\sa QXmlSerializer
*/
QXmlFormatter::QXmlFormatter(const QXmlQuery &query,
QIODevice *outputDevice) : QXmlSerializer(new QXmlFormatterPrivate(query, outputDevice))
{
}
/*!
\internal
*/
void QXmlFormatter::startFormattingContent()
{
Q_D(QXmlFormatter);
if(QPatternist::XPathHelper::isWhitespaceOnly(d->characterBuffer))
{
if(d->canIndent.top())
QXmlSerializer::characters(QStringRef(&d->indentString));
}
else
{
if(!d->characterBuffer.isEmpty()) /* Significant data, we don't touch it. */
QXmlSerializer::characters(QStringRef(&d->characterBuffer));
}
d->characterBuffer.clear();
}
/*!
\reimp
*/
void QXmlFormatter::startElement(const QXmlName &name)
{
Q_D(QXmlFormatter);
startFormattingContent();
++d->currentDepth;
d->indentString.append(QString(d->indentationDepth, QLatin1Char(' ')));
d->canIndent.push(true);
QXmlSerializer::startElement(name);
}
/*!
\reimp
*/
void QXmlFormatter::endElement()
{
Q_D(QXmlFormatter);
--d->currentDepth;
d->indentString.chop(d->indentationDepth);
if(!d->hasClosedElement.top().second)
d->canIndent.top() = false;
startFormattingContent();
d->canIndent.pop();
d->canIndent.top() = true;
QXmlSerializer::endElement();
}
/*!
\reimp
*/
void QXmlFormatter::attribute(const QXmlName &name,
const QStringRef &value)
{
QXmlSerializer::attribute(name, value);
}
/*!
\reimp
*/
void QXmlFormatter::comment(const QString &value)
{
Q_D(QXmlFormatter);
startFormattingContent();
QXmlSerializer::comment(value);
d->canIndent.top() = true;
}
/*!
\reimp
*/
void QXmlFormatter::characters(const QStringRef &value)
{
Q_D(QXmlFormatter);
d->isPreviousAtomic = false;
d->characterBuffer += value.toString();
}
/*!
\reimp
*/
void QXmlFormatter::processingInstruction(const QXmlName &name,
const QString &value)
{
Q_D(QXmlFormatter);
startFormattingContent();
QXmlSerializer::processingInstruction(name, value);
d->canIndent.top() = true;
}
/*!
\reimp
*/
void QXmlFormatter::atomicValue(const QVariant &value)
{
Q_D(QXmlFormatter);
d->canIndent.top() = false;
QXmlSerializer::atomicValue(value);
}
/*!
\reimp
*/
void QXmlFormatter::startDocument()
{
QXmlSerializer::startDocument();
}
/*!
\reimp
*/
void QXmlFormatter::endDocument()
{
QXmlSerializer::endDocument();
}
/*!
\reimp
*/
void QXmlFormatter::startOfSequence()
{
QXmlSerializer::startOfSequence();
}
/*!
\reimp
*/
void QXmlFormatter::endOfSequence()
{
Q_D(QXmlFormatter);
/* Flush any buffered content. */
if(!d->characterBuffer.isEmpty())
QXmlSerializer::characters(QStringRef(&d->characterBuffer));
d->write('\n');
QXmlSerializer::endOfSequence();
}
/*!
\internal
*/
void QXmlFormatter::item(const QPatternist::Item &item)
{
Q_D(QXmlFormatter);
if(item.isAtomicValue())
{
if(QPatternist::XPathHelper::isWhitespaceOnly(item.stringValue()))
return;
else
{
d->canIndent.top() = false;
startFormattingContent();
}
}
QXmlSerializer::item(item);
}
/*!
Returns the number of spaces QXmlFormatter will output for each
indentation level. The default is four.
\sa setIndentationDepth()
*/
int QXmlFormatter::indentationDepth() const
{
Q_D(const QXmlFormatter);
return d->indentationDepth;
}
/*!
Sets \a depth to be the number of spaces QXmlFormatter will
output for level of indentation. The default is four.
\sa indentationDepth()
*/
void QXmlFormatter::setIndentationDepth(int depth)
{
Q_D(QXmlFormatter);
d->indentationDepth = depth;
}
QT_END_NAMESPACE