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diff --git a/src/corelib/serialization/qjsonobject.cpp b/src/corelib/serialization/qjsonobject.cpp new file mode 100644 index 0000000000..4a316c8a6f --- /dev/null +++ b/src/corelib/serialization/qjsonobject.cpp @@ -0,0 +1,1312 @@ +/**************************************************************************** +** +** Copyright (C) 2016 The Qt Company Ltd. +** Contact: https://www.qt.io/licensing/ +** +** This file is part of the QtCore module of the Qt Toolkit. +** +** $QT_BEGIN_LICENSE:LGPL$ +** Commercial License Usage +** Licensees holding valid commercial Qt licenses may use this file in +** accordance with the commercial license agreement provided with the +** Software or, alternatively, in accordance with the terms contained in +** a written agreement between you and The Qt Company. For licensing terms +** and conditions see https://www.qt.io/terms-conditions. For further +** information use the contact form at https://www.qt.io/contact-us. +** +** GNU Lesser General Public License Usage +** Alternatively, this file may be used under the terms of the GNU Lesser +** General Public License version 3 as published by the Free Software +** Foundation and appearing in the file LICENSE.LGPL3 included in the +** packaging of this file. Please review the following information to +** ensure the GNU Lesser General Public License version 3 requirements +** will be met: https://www.gnu.org/licenses/lgpl-3.0.html. +** +** GNU General Public License Usage +** Alternatively, this file may be used under the terms of the GNU +** General Public License version 2.0 or (at your option) the GNU General +** Public license version 3 or any later version approved by the KDE Free +** Qt Foundation. The licenses are as published by the Free Software +** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3 +** included in the packaging of this file. Please review the following +** information to ensure the GNU General Public License requirements will +** be met: https://www.gnu.org/licenses/gpl-2.0.html and +** https://www.gnu.org/licenses/gpl-3.0.html. +** +** $QT_END_LICENSE$ +** +****************************************************************************/ + +#include <qjsonobject.h> +#include <qjsonvalue.h> +#include <qjsonarray.h> +#include <qstringlist.h> +#include <qdebug.h> +#include <qvariant.h> +#include "qjson_p.h" +#include "qjsonwriter_p.h" + +QT_BEGIN_NAMESPACE + +/*! + \class QJsonObject + \inmodule QtCore + \ingroup json + \ingroup shared + \reentrant + \since 5.0 + + \brief The QJsonObject class encapsulates a JSON object. + + A JSON object is a list of key value pairs, where the keys are unique strings + and the values are represented by a QJsonValue. + + A QJsonObject can be converted to and from a QVariantMap. You can query the + number of (key, value) pairs with size(), insert(), and remove() entries from it + and iterate over its content using the standard C++ iterator pattern. + + QJsonObject is an implicitly shared class, and shares the data with the document + it has been created from as long as it is not being modified. + + You can convert the object to and from text based JSON through QJsonDocument. + + \sa {JSON Support in Qt}, {JSON Save Game Example} +*/ + +/*! + \typedef QJsonObject::Iterator + + Qt-style synonym for QJsonObject::iterator. +*/ + +/*! + \typedef QJsonObject::ConstIterator + + Qt-style synonym for QJsonObject::const_iterator. +*/ + +/*! + \typedef QJsonObject::key_type + + Typedef for QString. Provided for STL compatibility. +*/ + +/*! + \typedef QJsonObject::mapped_type + + Typedef for QJsonValue. Provided for STL compatibility. +*/ + +/*! + \typedef QJsonObject::size_type + + Typedef for int. Provided for STL compatibility. +*/ + + +/*! + Constructs an empty JSON object. + + \sa isEmpty() + */ +QJsonObject::QJsonObject() + : d(0), o(0) +{ +} + +/*! + \fn QJsonObject::QJsonObject(std::initializer_list<QPair<QString, QJsonValue> > args) + \since 5.4 + Constructs a QJsonObject instance initialized from \a args initialization list. + For example: + \code + QJsonObject object + { + {"property1", 1}, + {"property2", 2} + }; + \endcode +*/ + +/*! + \internal + */ +QJsonObject::QJsonObject(QJsonPrivate::Data *data, QJsonPrivate::Object *object) + : d(data), o(object) +{ + Q_ASSERT(d); + Q_ASSERT(o); + d->ref.ref(); +} + +/*! + This method replaces part of the QJsonObject(std::initializer_list<QPair<QString, QJsonValue>> args) body. + The constructor needs to be inline, but we do not want to leak implementation details + of this class. + \note this method is called for an uninitialized object + \internal + */ + +void QJsonObject::initialize() +{ + d = 0; + o = 0; +} + +/*! + Destroys the object. + */ +QJsonObject::~QJsonObject() +{ + if (d && !d->ref.deref()) + delete d; +} + +/*! + Creates a copy of \a other. + + Since QJsonObject is implicitly shared, the copy is shallow + as long as the object does not get modified. + */ +QJsonObject::QJsonObject(const QJsonObject &other) +{ + d = other.d; + o = other.o; + if (d) + d->ref.ref(); +} + +/*! + Assigns \a other to this object. + */ +QJsonObject &QJsonObject::operator =(const QJsonObject &other) +{ + if (d != other.d) { + if (d && !d->ref.deref()) + delete d; + d = other.d; + if (d) + d->ref.ref(); + } + o = other.o; + + return *this; +} + +/*! + \fn QJsonObject::QJsonObject(QJsonObject &&other) + \since 5.10 + + Move-constructs a QJsonObject from \a other. +*/ + +/*! + \fn QJsonObject &QJsonObject::operator =(QJsonObject &&other) + \since 5.10 + + Move-assigns \a other to this object. +*/ + +/*! + \fn void QJsonObject::swap(QJsonObject &other) + \since 5.10 + + Swaps the object \a other with this. This operation is very fast and never fails. +*/ + + +/*! + Converts the variant map \a map to a QJsonObject. + + The keys in \a map will be used as the keys in the JSON object, + and the QVariant values will be converted to JSON values. + + \sa fromVariantHash(), toVariantMap(), QJsonValue::fromVariant() + */ +QJsonObject QJsonObject::fromVariantMap(const QVariantMap &map) +{ + QJsonObject object; + if (map.isEmpty()) + return object; + + object.detach2(1024); + + QVector<QJsonPrivate::offset> offsets; + QJsonPrivate::offset currentOffset; + currentOffset = sizeof(QJsonPrivate::Base); + + // the map is already sorted, so we can simply append one entry after the other and + // write the offset table at the end + for (QVariantMap::const_iterator it = map.constBegin(); it != map.constEnd(); ++it) { + QString key = it.key(); + QJsonValue val = QJsonValue::fromVariant(it.value()); + + bool latinOrIntValue; + int valueSize = QJsonPrivate::Value::requiredStorage(val, &latinOrIntValue); + + bool latinKey = QJsonPrivate::useCompressed(key); + int valueOffset = sizeof(QJsonPrivate::Entry) + QJsonPrivate::qStringSize(key, latinKey); + int requiredSize = valueOffset + valueSize; + + if (!object.detach2(requiredSize + sizeof(QJsonPrivate::offset))) // offset for the new index entry + return QJsonObject(); + + QJsonPrivate::Entry *e = reinterpret_cast<QJsonPrivate::Entry *>(reinterpret_cast<char *>(object.o) + currentOffset); + e->value.type = val.t; + e->value.latinKey = latinKey; + e->value.latinOrIntValue = latinOrIntValue; + e->value.value = QJsonPrivate::Value::valueToStore(val, (char *)e - (char *)object.o + valueOffset); + QJsonPrivate::copyString((char *)(e + 1), key, latinKey); + if (valueSize) + QJsonPrivate::Value::copyData(val, (char *)e + valueOffset, latinOrIntValue); + + offsets << currentOffset; + currentOffset += requiredSize; + object.o->size = currentOffset; + } + + // write table + object.o->tableOffset = currentOffset; + if (!object.detach2(sizeof(QJsonPrivate::offset)*offsets.size())) + return QJsonObject(); + memcpy(object.o->table(), offsets.constData(), offsets.size()*sizeof(uint)); + object.o->length = offsets.size(); + object.o->size = currentOffset + sizeof(QJsonPrivate::offset)*offsets.size(); + + return object; +} + +/*! + Converts this object to a QVariantMap. + + Returns the created map. + + \sa toVariantHash() + */ +QVariantMap QJsonObject::toVariantMap() const +{ + QVariantMap map; + if (o) { + for (uint i = 0; i < o->length; ++i) { + QJsonPrivate::Entry *e = o->entryAt(i); + map.insert(e->key(), QJsonValue(d, o, e->value).toVariant()); + } + } + return map; +} + +/*! + Converts the variant hash \a hash to a QJsonObject. + \since 5.5 + + The keys in \a hash will be used as the keys in the JSON object, + and the QVariant values will be converted to JSON values. + + \sa fromVariantMap(), toVariantHash(), QJsonValue::fromVariant() + */ +QJsonObject QJsonObject::fromVariantHash(const QVariantHash &hash) +{ + // ### this is implemented the trivial way, not the most efficient way + + QJsonObject object; + for (QVariantHash::const_iterator it = hash.constBegin(); it != hash.constEnd(); ++it) + object.insert(it.key(), QJsonValue::fromVariant(it.value())); + return object; +} + +/*! + Converts this object to a QVariantHash. + \since 5.5 + + Returns the created hash. + + \sa toVariantMap() + */ +QVariantHash QJsonObject::toVariantHash() const +{ + QVariantHash hash; + if (o) { + hash.reserve(o->length); + for (uint i = 0; i < o->length; ++i) { + QJsonPrivate::Entry *e = o->entryAt(i); + hash.insert(e->key(), QJsonValue(d, o, e->value).toVariant()); + } + } + return hash; +} + +/*! + Returns a list of all keys in this object. + + The list is sorted lexographically. + */ +QStringList QJsonObject::keys() const +{ + QStringList keys; + if (o) { + keys.reserve(o->length); + for (uint i = 0; i < o->length; ++i) { + QJsonPrivate::Entry *e = o->entryAt(i); + keys.append(e->key()); + } + } + return keys; +} + +/*! + Returns the number of (key, value) pairs stored in the object. + */ +int QJsonObject::size() const +{ + if (!d) + return 0; + + return o->length; +} + +/*! + Returns \c true if the object is empty. This is the same as size() == 0. + + \sa size() + */ +bool QJsonObject::isEmpty() const +{ + if (!d) + return true; + + return !o->length; +} + +/*! + Returns a QJsonValue representing the value for the key \a key. + + The returned QJsonValue is QJsonValue::Undefined if the key does not exist. + + \sa QJsonValue, QJsonValue::isUndefined() + */ +QJsonValue QJsonObject::value(const QString &key) const +{ + if (!d) + return QJsonValue(QJsonValue::Undefined); + + bool keyExists; + int i = o->indexOf(key, &keyExists); + if (!keyExists) + return QJsonValue(QJsonValue::Undefined); + return QJsonValue(d, o, o->entryAt(i)->value); +} + +/*! + \overload + \since 5.7 +*/ +QJsonValue QJsonObject::value(QLatin1String key) const +{ + if (!d) + return QJsonValue(QJsonValue::Undefined); + + bool keyExists; + int i = o->indexOf(key, &keyExists); + if (!keyExists) + return QJsonValue(QJsonValue::Undefined); + return QJsonValue(d, o, o->entryAt(i)->value); +} + +/*! + Returns a QJsonValue representing the value for the key \a key. + + This does the same as value(). + + The returned QJsonValue is QJsonValue::Undefined if the key does not exist. + + \sa value(), QJsonValue, QJsonValue::isUndefined() + */ +QJsonValue QJsonObject::operator [](const QString &key) const +{ + return value(key); +} + +/*! + \fn QJsonValue QJsonObject::operator [](QLatin1String key) const + + \overload + \since 5.7 +*/ + +/*! + Returns a reference to the value for \a key. + + The return value is of type QJsonValueRef, a helper class for QJsonArray + and QJsonObject. When you get an object of type QJsonValueRef, you can + use it as if it were a reference to a QJsonValue. If you assign to it, + the assignment will apply to the element in the QJsonArray or QJsonObject + from which you got the reference. + + \sa value() + */ +QJsonValueRef QJsonObject::operator [](const QString &key) +{ + // ### somewhat inefficient, as we lookup the key twice if it doesn't yet exist + bool keyExists = false; + int index = o ? o->indexOf(key, &keyExists) : -1; + if (!keyExists) { + iterator i = insert(key, QJsonValue()); + index = i.i; + } + return QJsonValueRef(this, index); +} + +/*! + \overload + \since 5.7 +*/ +QJsonValueRef QJsonObject::operator [](QLatin1String key) +{ + // ### optimize me + return operator[](QString(key)); +} + +/*! + Inserts a new item with the key \a key and a value of \a value. + + If there is already an item with the key \a key, then that item's value + is replaced with \a value. + + Returns an iterator pointing to the inserted item. + + If the value is QJsonValue::Undefined, it will cause the key to get removed + from the object. The returned iterator will then point to end(). + + \sa remove(), take(), QJsonObject::iterator, end() + */ +QJsonObject::iterator QJsonObject::insert(const QString &key, const QJsonValue &value) +{ + if (value.t == QJsonValue::Undefined) { + remove(key); + return end(); + } + QJsonValue val = value; + + bool latinOrIntValue; + int valueSize = QJsonPrivate::Value::requiredStorage(val, &latinOrIntValue); + + bool latinKey = QJsonPrivate::useCompressed(key); + int valueOffset = sizeof(QJsonPrivate::Entry) + QJsonPrivate::qStringSize(key, latinKey); + int requiredSize = valueOffset + valueSize; + + if (!detach2(requiredSize + sizeof(QJsonPrivate::offset))) // offset for the new index entry + return iterator(); + + if (!o->length) + o->tableOffset = sizeof(QJsonPrivate::Object); + + bool keyExists = false; + int pos = o->indexOf(key, &keyExists); + if (keyExists) + ++d->compactionCounter; + + uint off = o->reserveSpace(requiredSize, pos, 1, keyExists); + if (!off) + return end(); + + QJsonPrivate::Entry *e = o->entryAt(pos); + e->value.type = val.t; + e->value.latinKey = latinKey; + e->value.latinOrIntValue = latinOrIntValue; + e->value.value = QJsonPrivate::Value::valueToStore(val, (char *)e - (char *)o + valueOffset); + QJsonPrivate::copyString((char *)(e + 1), key, latinKey); + if (valueSize) + QJsonPrivate::Value::copyData(val, (char *)e + valueOffset, latinOrIntValue); + + if (d->compactionCounter > 32u && d->compactionCounter >= unsigned(o->length) / 2u) + compact(); + + return iterator(this, pos); +} + +/*! + Removes \a key from the object. + + \sa insert(), take() + */ +void QJsonObject::remove(const QString &key) +{ + if (!d) + return; + + bool keyExists; + int index = o->indexOf(key, &keyExists); + if (!keyExists) + return; + + detach2(); + o->removeItems(index, 1); + ++d->compactionCounter; + if (d->compactionCounter > 32u && d->compactionCounter >= unsigned(o->length) / 2u) + compact(); +} + +/*! + Removes \a key from the object. + + Returns a QJsonValue containing the value referenced by \a key. + If \a key was not contained in the object, the returned QJsonValue + is QJsonValue::Undefined. + + \sa insert(), remove(), QJsonValue + */ +QJsonValue QJsonObject::take(const QString &key) +{ + if (!o) + return QJsonValue(QJsonValue::Undefined); + + bool keyExists; + int index = o->indexOf(key, &keyExists); + if (!keyExists) + return QJsonValue(QJsonValue::Undefined); + + QJsonValue v(d, o, o->entryAt(index)->value); + detach2(); + o->removeItems(index, 1); + ++d->compactionCounter; + if (d->compactionCounter > 32u && d->compactionCounter >= unsigned(o->length) / 2u) + compact(); + + return v; +} + +/*! + Returns \c true if the object contains key \a key. + + \sa insert(), remove(), take() + */ +bool QJsonObject::contains(const QString &key) const +{ + if (!o) + return false; + + bool keyExists; + o->indexOf(key, &keyExists); + return keyExists; +} + +/*! + \overload + \since 5.7 +*/ +bool QJsonObject::contains(QLatin1String key) const +{ + if (!o) + return false; + + bool keyExists; + o->indexOf(key, &keyExists); + return keyExists; +} + +/*! + Returns \c true if \a other is equal to this object. + */ +bool QJsonObject::operator==(const QJsonObject &other) const +{ + if (o == other.o) + return true; + + if (!o) + return !other.o->length; + if (!other.o) + return !o->length; + if (o->length != other.o->length) + return false; + + for (uint i = 0; i < o->length; ++i) { + QJsonPrivate::Entry *e = o->entryAt(i); + QJsonValue v(d, o, e->value); + if (other.value(e->key()) != v) + return false; + } + + return true; +} + +/*! + Returns \c true if \a other is not equal to this object. + */ +bool QJsonObject::operator!=(const QJsonObject &other) const +{ + return !(*this == other); +} + +/*! + Removes the (key, value) pair pointed to by the iterator \a it + from the map, and returns an iterator to the next item in the + map. + + \sa remove() + */ +QJsonObject::iterator QJsonObject::erase(QJsonObject::iterator it) +{ + Q_ASSERT(d && d->ref.load() == 1); + if (it.o != this || it.i < 0 || it.i >= (int)o->length) + return iterator(this, o->length); + + int index = it.i; + + o->removeItems(index, 1); + ++d->compactionCounter; + if (d->compactionCounter > 32u && d->compactionCounter >= unsigned(o->length) / 2u) + compact(); + + // iterator hasn't changed + return it; +} + +/*! + Returns an iterator pointing to the item with key \a key in the + map. + + If the map contains no item with key \a key, the function + returns end(). + */ +QJsonObject::iterator QJsonObject::find(const QString &key) +{ + bool keyExists = false; + int index = o ? o->indexOf(key, &keyExists) : 0; + if (!keyExists) + return end(); + detach2(); + return iterator(this, index); +} + +/*! + \overload + \since 5.7 +*/ +QJsonObject::iterator QJsonObject::find(QLatin1String key) +{ + bool keyExists = false; + int index = o ? o->indexOf(key, &keyExists) : 0; + if (!keyExists) + return end(); + detach2(); + return iterator(this, index); +} + +/*! \fn QJsonObject::const_iterator QJsonObject::find(const QString &key) const + + \overload +*/ + +/*! \fn QJsonObject::const_iterator QJsonObject::find(QLatin1String key) const + + \overload + \since 5.7 +*/ + +/*! + Returns a const iterator pointing to the item with key \a key in the + map. + + If the map contains no item with key \a key, the function + returns constEnd(). + */ +QJsonObject::const_iterator QJsonObject::constFind(const QString &key) const +{ + bool keyExists = false; + int index = o ? o->indexOf(key, &keyExists) : 0; + if (!keyExists) + return end(); + return const_iterator(this, index); +} + +/*! + \overload + \since 5.7 +*/ +QJsonObject::const_iterator QJsonObject::constFind(QLatin1String key) const +{ + bool keyExists = false; + int index = o ? o->indexOf(key, &keyExists) : 0; + if (!keyExists) + return end(); + return const_iterator(this, index); +} + +/*! \fn int QJsonObject::count() const + + \overload + + Same as size(). +*/ + +/*! \fn int QJsonObject::length() const + + \overload + + Same as size(). +*/ + +/*! \fn QJsonObject::iterator QJsonObject::begin() + + Returns an \l{STL-style iterators}{STL-style iterator} pointing to the first item in + the object. + + \sa constBegin(), end() +*/ + +/*! \fn QJsonObject::const_iterator QJsonObject::begin() const + + \overload +*/ + +/*! \fn QJsonObject::const_iterator QJsonObject::constBegin() const + + Returns a const \l{STL-style iterators}{STL-style iterator} pointing to the first item + in the object. + + \sa begin(), constEnd() +*/ + +/*! \fn QJsonObject::iterator QJsonObject::end() + + Returns an \l{STL-style iterators}{STL-style iterator} pointing to the imaginary item + after the last item in the object. + + \sa begin(), constEnd() +*/ + +/*! \fn QJsonObject::const_iterator QJsonObject::end() const + + \overload +*/ + +/*! \fn QJsonObject::const_iterator QJsonObject::constEnd() const + + Returns a const \l{STL-style iterators}{STL-style iterator} pointing to the imaginary + item after the last item in the object. + + \sa constBegin(), end() +*/ + +/*! + \fn bool QJsonObject::empty() const + + This function is provided for STL compatibility. It is equivalent + to isEmpty(), returning \c true if the object is empty; otherwise + returning \c false. +*/ + +/*! \class QJsonObject::iterator + \inmodule QtCore + \ingroup json + \reentrant + \since 5.0 + + \brief The QJsonObject::iterator class provides an STL-style non-const iterator for QJsonObject. + + QJsonObject::iterator allows you to iterate over a QJsonObject + and to modify the value (but not the key) stored under + a particular key. If you want to iterate over a const QJsonObject, you + should use QJsonObject::const_iterator. It is generally good practice to + use QJsonObject::const_iterator on a non-const QJsonObject as well, unless you + need to change the QJsonObject through the iterator. Const iterators are + slightly faster, and improve code readability. + + The default QJsonObject::iterator constructor creates an uninitialized + iterator. You must initialize it using a QJsonObject function like + QJsonObject::begin(), QJsonObject::end(), or QJsonObject::find() before you can + start iterating. + + Multiple iterators can be used on the same object. Existing iterators will however + become dangling once the object gets modified. + + \sa QJsonObject::const_iterator, {JSON Support in Qt}, {JSON Save Game Example} +*/ + +/*! \typedef QJsonObject::iterator::difference_type + + \internal +*/ + +/*! \typedef QJsonObject::iterator::iterator_category + + A synonym for \e {std::random_access_iterator_tag} indicating + this iterator is a random-access iterator. + + \note In Qt versions before 5.6, this was set by mistake to + \e {std::bidirectional_iterator_tag}. +*/ + +/*! \typedef QJsonObject::iterator::reference + + \internal +*/ + +/*! \typedef QJsonObject::iterator::value_type + + \internal +*/ + +/*! \typedef QJsonObject::iterator::pointer + + \internal +*/ + +/*! \fn QJsonObject::iterator::iterator() + + Constructs an uninitialized iterator. + + Functions like key(), value(), and operator++() must not be + called on an uninitialized iterator. Use operator=() to assign a + value to it before using it. + + \sa QJsonObject::begin(), QJsonObject::end() +*/ + +/*! \fn QJsonObject::iterator::iterator(QJsonObject *obj, int index) + \internal +*/ + +/*! \fn QString QJsonObject::iterator::key() const + + Returns the current item's key. + + There is no direct way of changing an item's key through an + iterator, although it can be done by calling QJsonObject::erase() + followed by QJsonObject::insert(). + + \sa value() +*/ + +/*! \fn QJsonValueRef QJsonObject::iterator::value() const + + Returns a modifiable reference to the current item's value. + + You can change the value of an item by using value() on + the left side of an assignment. + + The return value is of type QJsonValueRef, a helper class for QJsonArray + and QJsonObject. When you get an object of type QJsonValueRef, you can + use it as if it were a reference to a QJsonValue. If you assign to it, + the assignment will apply to the element in the QJsonArray or QJsonObject + from which you got the reference. + + \sa key(), operator*() +*/ + +/*! \fn QJsonValueRef QJsonObject::iterator::operator*() const + + Returns a modifiable reference to the current item's value. + + Same as value(). + + The return value is of type QJsonValueRef, a helper class for QJsonArray + and QJsonObject. When you get an object of type QJsonValueRef, you can + use it as if it were a reference to a QJsonValue. If you assign to it, + the assignment will apply to the element in the QJsonArray or QJsonObject + from which you got the reference. + + \sa key() +*/ + +/*! \fn QJsonValueRef *QJsonObject::iterator::operator->() const + + Returns a pointer to a modifiable reference to the current item. +*/ + +/*! + \fn bool QJsonObject::iterator::operator==(const iterator &other) const + \fn bool QJsonObject::iterator::operator==(const const_iterator &other) const + + Returns \c true if \a other points to the same item as this + iterator; otherwise returns \c false. + + \sa operator!=() +*/ + +/*! + \fn bool QJsonObject::iterator::operator!=(const iterator &other) const + \fn bool QJsonObject::iterator::operator!=(const const_iterator &other) const + + Returns \c true if \a other points to a different item than this + iterator; otherwise returns \c false. + + \sa operator==() +*/ + +/*! \fn QJsonObject::iterator QJsonObject::iterator::operator++() + + The prefix ++ operator, \c{++i}, advances the iterator to the + next item in the object and returns an iterator to the new current + item. + + Calling this function on QJsonObject::end() leads to undefined results. + + \sa operator--() +*/ + +/*! \fn QJsonObject::iterator QJsonObject::iterator::operator++(int) + + \overload + + The postfix ++ operator, \c{i++}, advances the iterator to the + next item in the object and returns an iterator to the previously + current item. +*/ + +/*! \fn QJsonObject::iterator QJsonObject::iterator::operator--() + + The prefix -- operator, \c{--i}, makes the preceding item + current and returns an iterator pointing to the new current item. + + Calling this function on QJsonObject::begin() leads to undefined + results. + + \sa operator++() +*/ + +/*! \fn QJsonObject::iterator QJsonObject::iterator::operator--(int) + + \overload + + The postfix -- operator, \c{i--}, makes the preceding item + current and returns an iterator pointing to the previously + current item. +*/ + +/*! \fn QJsonObject::iterator QJsonObject::iterator::operator+(int j) const + + Returns an iterator to the item at \a j positions forward from + this iterator. If \a j is negative, the iterator goes backward. + + \sa operator-() + +*/ + +/*! \fn QJsonObject::iterator QJsonObject::iterator::operator-(int j) const + + Returns an iterator to the item at \a j positions backward from + this iterator. If \a j is negative, the iterator goes forward. + + \sa operator+() +*/ + +/*! \fn QJsonObject::iterator &QJsonObject::iterator::operator+=(int j) + + Advances the iterator by \a j items. If \a j is negative, the + iterator goes backward. + + \sa operator-=(), operator+() +*/ + +/*! \fn QJsonObject::iterator &QJsonObject::iterator::operator-=(int j) + + Makes the iterator go back by \a j items. If \a j is negative, + the iterator goes forward. + + \sa operator+=(), operator-() +*/ + +/*! + \class QJsonObject::const_iterator + \inmodule QtCore + \ingroup json + \since 5.0 + \brief The QJsonObject::const_iterator class provides an STL-style const iterator for QJsonObject. + + QJsonObject::const_iterator allows you to iterate over a QJsonObject. + If you want to modify the QJsonObject as you iterate + over it, you must use QJsonObject::iterator instead. It is generally + good practice to use QJsonObject::const_iterator on a non-const QJsonObject as + well, unless you need to change the QJsonObject through the iterator. + Const iterators are slightly faster and improve code + readability. + + The default QJsonObject::const_iterator constructor creates an + uninitialized iterator. You must initialize it using a QJsonObject + function like QJsonObject::constBegin(), QJsonObject::constEnd(), or + QJsonObject::find() before you can start iterating. + + Multiple iterators can be used on the same object. Existing iterators + will however become dangling if the object gets modified. + + \sa QJsonObject::iterator, {JSON Support in Qt}, {JSON Save Game Example} +*/ + +/*! \typedef QJsonObject::const_iterator::difference_type + + \internal +*/ + +/*! \typedef QJsonObject::const_iterator::iterator_category + + A synonym for \e {std::random_access_iterator_tag} indicating + this iterator is a random-access iterator. + + \note In Qt versions before 5.6, this was set by mistake to + \e {std::bidirectional_iterator_tag}. +*/ + +/*! \typedef QJsonObject::const_iterator::reference + + \internal +*/ + +/*! \typedef QJsonObject::const_iterator::value_type + + \internal +*/ + +/*! \typedef QJsonObject::const_iterator::pointer + + \internal +*/ + +/*! \fn QJsonObject::const_iterator::const_iterator() + + Constructs an uninitialized iterator. + + Functions like key(), value(), and operator++() must not be + called on an uninitialized iterator. Use operator=() to assign a + value to it before using it. + + \sa QJsonObject::constBegin(), QJsonObject::constEnd() +*/ + +/*! \fn QJsonObject::const_iterator::const_iterator(const QJsonObject *obj, int index) + \internal +*/ + +/*! \fn QJsonObject::const_iterator::const_iterator(const iterator &other) + + Constructs a copy of \a other. +*/ + +/*! \fn QString QJsonObject::const_iterator::key() const + + Returns the current item's key. + + \sa value() +*/ + +/*! \fn QJsonValue QJsonObject::const_iterator::value() const + + Returns the current item's value. + + \sa key(), operator*() +*/ + +/*! \fn QJsonValue QJsonObject::const_iterator::operator*() const + + Returns the current item's value. + + Same as value(). + + \sa key() +*/ + +/*! \fn QJsonValue *QJsonObject::const_iterator::operator->() const + + Returns a pointer to the current item. +*/ + +/*! \fn bool QJsonObject::const_iterator::operator==(const const_iterator &other) const + \fn bool QJsonObject::const_iterator::operator==(const iterator &other) const + + Returns \c true if \a other points to the same item as this + iterator; otherwise returns \c false. + + \sa operator!=() +*/ + +/*! \fn bool QJsonObject::const_iterator::operator!=(const const_iterator &other) const + \fn bool QJsonObject::const_iterator::operator!=(const iterator &other) const + + Returns \c true if \a other points to a different item than this + iterator; otherwise returns \c false. + + \sa operator==() +*/ + +/*! \fn QJsonObject::const_iterator QJsonObject::const_iterator::operator++() + + The prefix ++ operator, \c{++i}, advances the iterator to the + next item in the object and returns an iterator to the new current + item. + + Calling this function on QJsonObject::end() leads to undefined results. + + \sa operator--() +*/ + +/*! \fn QJsonObject::const_iterator QJsonObject::const_iterator::operator++(int) + + \overload + + The postfix ++ operator, \c{i++}, advances the iterator to the + next item in the object and returns an iterator to the previously + current item. +*/ + +/*! \fn QJsonObject::const_iterator &QJsonObject::const_iterator::operator--() + + The prefix -- operator, \c{--i}, makes the preceding item + current and returns an iterator pointing to the new current item. + + Calling this function on QJsonObject::begin() leads to undefined + results. + + \sa operator++() +*/ + +/*! \fn QJsonObject::const_iterator QJsonObject::const_iterator::operator--(int) + + \overload + + The postfix -- operator, \c{i--}, makes the preceding item + current and returns an iterator pointing to the previously + current item. +*/ + +/*! \fn QJsonObject::const_iterator QJsonObject::const_iterator::operator+(int j) const + + Returns an iterator to the item at \a j positions forward from + this iterator. If \a j is negative, the iterator goes backward. + + This operation can be slow for large \a j values. + + \sa operator-() +*/ + +/*! \fn QJsonObject::const_iterator QJsonObject::const_iterator::operator-(int j) const + + Returns an iterator to the item at \a j positions backward from + this iterator. If \a j is negative, the iterator goes forward. + + This operation can be slow for large \a j values. + + \sa operator+() +*/ + +/*! \fn QJsonObject::const_iterator &QJsonObject::const_iterator::operator+=(int j) + + Advances the iterator by \a j items. If \a j is negative, the + iterator goes backward. + + This operation can be slow for large \a j values. + + \sa operator-=(), operator+() +*/ + +/*! \fn QJsonObject::const_iterator &QJsonObject::const_iterator::operator-=(int j) + + Makes the iterator go back by \a j items. If \a j is negative, + the iterator goes forward. + + This operation can be slow for large \a j values. + + \sa operator+=(), operator-() +*/ + + +/*! + \internal + */ +void QJsonObject::detach(uint reserve) +{ + Q_UNUSED(reserve) + Q_ASSERT(!reserve); + detach2(reserve); +} + +bool QJsonObject::detach2(uint reserve) +{ + if (!d) { + if (reserve >= QJsonPrivate::Value::MaxSize) { + qWarning("QJson: Document too large to store in data structure"); + return false; + } + d = new QJsonPrivate::Data(reserve, QJsonValue::Object); + o = static_cast<QJsonPrivate::Object *>(d->header->root()); + d->ref.ref(); + return true; + } + if (reserve == 0 && d->ref.load() == 1) + return true; + + QJsonPrivate::Data *x = d->clone(o, reserve); + if (!x) + return false; + x->ref.ref(); + if (!d->ref.deref()) + delete d; + d = x; + o = static_cast<QJsonPrivate::Object *>(d->header->root()); + return true; +} + +/*! + \internal + */ +void QJsonObject::compact() +{ + if (!d || !d->compactionCounter) + return; + + detach2(); + d->compact(); + o = static_cast<QJsonPrivate::Object *>(d->header->root()); +} + +/*! + \internal + */ +QString QJsonObject::keyAt(int i) const +{ + Q_ASSERT(o && i >= 0 && i < (int)o->length); + + QJsonPrivate::Entry *e = o->entryAt(i); + return e->key(); +} + +/*! + \internal + */ +QJsonValue QJsonObject::valueAt(int i) const +{ + if (!o || i < 0 || i >= (int)o->length) + return QJsonValue(QJsonValue::Undefined); + + QJsonPrivate::Entry *e = o->entryAt(i); + return QJsonValue(d, o, e->value); +} + +/*! + \internal + */ +void QJsonObject::setValueAt(int i, const QJsonValue &val) +{ + Q_ASSERT(o && i >= 0 && i < (int)o->length); + + QJsonPrivate::Entry *e = o->entryAt(i); + insert(e->key(), val); +} + +#if !defined(QT_NO_DEBUG_STREAM) && !defined(QT_JSON_READONLY) +QDebug operator<<(QDebug dbg, const QJsonObject &o) +{ + QDebugStateSaver saver(dbg); + if (!o.o) { + dbg << "QJsonObject()"; + return dbg; + } + QByteArray json; + QJsonPrivate::Writer::objectToJson(o.o, json, 0, true); + dbg.nospace() << "QJsonObject(" + << json.constData() // print as utf-8 string without extra quotation marks + << ")"; + return dbg; +} +#endif + +QT_END_NAMESPACE |