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#include <QMutex>

#include "private/qobject_p.h"

#include "qabstractmessagehandler.h"

QT_BEGIN_NAMESPACE

class QAbstractMessageHandlerPrivate : public QObjectPrivate

{

public:

    QMutex mutex;

};

/*!

  \class QAbstractMessageHandler

  \threadsafe

  \since 4.4

  \ingroup xml-tools

  \brief The QAbstractMessageHandler class provides a callback interface for handling messages.

  QAbstractMessageHandler is an abstract base class that provides a

  callback interface for handling messages. For example, class

  QXmlQuery parses and runs an XQuery. When it detects a compile

  or runtime error, it generates an appropriate error message,

  but rather than output the message itself, it passes the message to

  the message() function of its QAbstractMessageHandler.

  See QXmlQuery::setMessageHandler().

  You create a message handler by subclassing QAbstractMessageHandler

  and implementing handleMessage(). You then pass a pointer to an

  instance of your subclass to any classes that must generate

  messages. The messages are sent to the message handler via the

  message() function, which forwards them to your handleMessge().

  The effect is to serialize the handling of all messages, which

  means your QAbstractMessageHandler subclass is thread safe.

  A single instance of QAbstractMessageHandler can be called on to

  handle messages from multiple sources. Hence, the content of a

  message, which is the \e description parameter passed to message()

  and handleMessage(), must be interpreted in light of the context

  that required the message to be sent. That context is specified by

  the \e identifier and \e sourceLocation parameters to message()

  handleMessage().

 */

/*!

  Constructs a QAbstractMessageHandler. The \a parent is passed

  to the QObject base class constructor.

 */

QAbstractMessageHandler::QAbstractMessageHandler(QObject *parent) : QObject(*new QAbstractMessageHandlerPrivate(), parent)

{

}

/*!

  Destructs this QAbstractMessageHandler.

 */

QAbstractMessageHandler::~QAbstractMessageHandler()

{

}

/*!

  Sends a message to this message handler. \a type is the kind of

  message being sent. \a description is the message content. The \a

  identifier is a URI that identifies the message and is the key to

  interpreting the other arguments.

  Typically, this class is used for reporting errors, as is the case

  for QXmlQuery, which uses a QAbstractMessageHandler to report

  compile and runtime XQuery errors. Hence, using a QUrl as the

  message \a identifier is was inspired by the explanation of \l{error

  handling in the XQuery language}. Because the \a identifier is

  composed of a namespace URI and a local part, identifiers with the

  same local part are unique.  The caller is responsible for ensuring

  that \a identifier is either a valid QUrl or a default constructed

  QUrl.

  \a sourceLocation identifies a location in a resource (i.e., file or

  document) where the need for reporting a message was detected.

  This function unconditionally calls handleMessage(), passing all

  its parameters unmodified.

  \sa {http://www.w3.org/TR/xquery/#errors}

 */

void QAbstractMessageHandler::message(QtMsgType type,

                                      const QString &description,

                                      const QUrl &identifier,

                                      const QSourceLocation &sourceLocation)

{

    Q_D(QAbstractMessageHandler);

    QMutexLocker(&d->mutex);

    handleMessage(type, description, identifier, sourceLocation);

}

/*!

  \fn void QAbstractMessageHandler::handleMessage(QtMsgType type,

                                                  const QString &description,

                                                  const QUrl &identifier = QUrl(),

                                                  const QSourceLocation &sourceLocation = QSourceLocation()) = 0

  This function must be implemented by the sub-class. message() will

  call this function, passing in its parameters, \a type,

  \a description, \a identifier and \a sourceLocation unmodified.

 */

QT_END_NAMESPACE