include/QtCore/qjsonvalue.h

0001 // Copyright (C) 2016 The Qt Company Ltd.
0002 // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
0003
0004 #ifndef QJSONVALUE_H
0005 #define QJSONVALUE_H
0006
0007 #include <QtCore/qglobal.h>
0008 #include <QtCore/qstring.h>
0009 #include <QtCore/qshareddata.h>
0010 #include <QtCore/qcborvalue.h>
0011
0012 QT_BEGIN_NAMESPACE
0013
0014 class QVariant;
0015 class QJsonArray;
0016 class QJsonObject;
0017 class QCborContainerPrivate;
0018
0019 namespace QJsonPrivate {
0020 class Value;
0021 }
0022
0023 class Q_CORE_EXPORT QJsonValue
0024 {
0025 public:
0026     enum Type {
0027         Null =  0x0,
0028         Bool = 0x1,
0029         Double = 0x2,
0030         String = 0x3,
0031         Array = 0x4,
0032         Object = 0x5,
0033         Undefined = 0x80
0034     };
0035
0036     QJsonValue(Type = Null);
0037     QJsonValue(bool b);
0038     QJsonValue(double n);
0039     QJsonValue(int n);
0040     QJsonValue(qint64 v);
0041     QJsonValue(const QString &s);
0042     QJsonValue(QLatin1StringView s);
0043 #ifndef QT_NO_CAST_FROM_ASCII
0044     QT_ASCII_CAST_WARN inline QJsonValue(const char *s)
0045         : QJsonValue(QString::fromUtf8(s)) {}
0046 #endif
0047     QJsonValue(const QJsonArray &a);
0048     QJsonValue(QJsonArray &&a) noexcept;
0049     QJsonValue(const QJsonObject &o);
0050     QJsonValue(QJsonObject &&o) noexcept;
0051
0052     ~QJsonValue();
0053
0054     QJsonValue(const QJsonValue &other) noexcept;
0055     QJsonValue &operator =(const QJsonValue &other) noexcept;
0056
0057     QJsonValue(QJsonValue &&other) noexcept;
0058
0059     QJsonValue &operator =(QJsonValue &&other) noexcept
0060     {
0061         swap(other);
0062         return *this;
0063     }
0064
0065     void swap(QJsonValue &other) noexcept;
0066
0067     static QJsonValue fromVariant(const QVariant &variant);
0068     QVariant toVariant() const;
0069
0070     Type type() const;
0071     inline bool isNull() const { return type() == Null; }
0072     inline bool isBool() const { return type() == Bool; }
0073     inline bool isDouble() const { return type() == Double; }
0074     inline bool isString() const { return type() == String; }
0075     inline bool isArray() const { return type() == Array; }
0076     inline bool isObject() const { return type() == Object; }
0077     inline bool isUndefined() const { return type() == Undefined; }
0078
0079     bool toBool(bool defaultValue = false) const;
0080     int toInt(int defaultValue = 0) const;
0081     qint64 toInteger(qint64 defaultValue = 0) const;
0082     double toDouble(double defaultValue = 0) const;
0083     QString toString() const;
0084     QString toString(const QString &defaultValue) const;
0085     QJsonArray toArray() const;
0086     QJsonArray toArray(const QJsonArray &defaultValue) const;
0087     QJsonObject toObject() const;
0088     QJsonObject toObject(const QJsonObject &defaultValue) const;
0089
0090     const QJsonValue operator[](const QString &key) const;
0091     const QJsonValue operator[](QStringView key) const;
0092     const QJsonValue operator[](QLatin1StringView key) const;
0093     const QJsonValue operator[](qsizetype i) const;
0094
0095     bool operator==(const QJsonValue &other) const;
0096     bool operator!=(const QJsonValue &other) const;
0097
0098 private:
0099     // avoid implicit conversions from char * to bool
0100     QJsonValue(const void *) = delete;
0101     friend class QJsonPrivate::Value;
0102     friend class QJsonArray;
0103     friend class QJsonObject;
0104     friend class QCborValue;
0105     friend Q_CORE_EXPORT QDebug operator<<(QDebug, const QJsonValue &);
0106     friend Q_CORE_EXPORT QDataStream &operator<<(QDataStream &, const QJsonValue &);
0107
0108     QCborValue value;
0109
0110     // Assert binary compatibility with pre-5.15 QJsonValue
0111     static_assert(sizeof(QExplicitlySharedDataPointer<QCborContainerPrivate>) == sizeof(void *));
0112     static_assert(sizeof(QCborValue::Type) == sizeof(QJsonValue::Type));
0113 };
0114
0115 Q_DECLARE_SHARED(QJsonValue)
0116
0117 class QJsonValueConstRef
0118 {
0119 public:
0120     QJsonValueConstRef(const QJsonValueConstRef &) = default;
0121     QJsonValueConstRef &operator=(const QJsonValueConstRef &) = delete;
0122     inline operator QJsonValue() const { return concrete(*this); }
0123
0124     Q_CORE_EXPORT QVariant toVariant() const;
0125     QJsonValue::Type type() const { return concreteType(*this); }
0126     bool isNull() const { return type() == QJsonValue::Null; }
0127     bool isBool() const { return type() == QJsonValue::Bool; }
0128     bool isDouble() const { return type() == QJsonValue::Double; }
0129     bool isString() const { return type() == QJsonValue::String; }
0130     bool isArray() const { return type() == QJsonValue::Array; }
0131     bool isObject() const { return type() == QJsonValue::Object; }
0132     bool isUndefined() const { return type() == QJsonValue::Undefined; }
0133
0134     bool toBool(bool defaultValue = false) const
0135     { return concreteBool(*this, defaultValue); }
0136     int toInt(int defaultValue = 0) const
0137     { return int(concreteInt(*this, defaultValue, true)); }
0138     qint64 toInteger(qint64 defaultValue = 0) const
0139     { return concreteInt(*this, defaultValue, false); }
0140     double toDouble(double defaultValue = 0) const
0141     { return concreteDouble(*this, defaultValue); }
0142     QString toString(const QString &defaultValue = {}) const
0143     { return concreteString(*this, defaultValue); }
0144     Q_CORE_EXPORT QJsonArray toArray() const;
0145     Q_CORE_EXPORT QJsonObject toObject() const;
0146
0147     const QJsonValue operator[](QStringView key) const { return concrete(*this)[key]; }
0148     const QJsonValue operator[](QLatin1StringView key) const { return concrete(*this)[key]; }
0149     const QJsonValue operator[](qsizetype i) const { return concrete(*this)[i]; }
0150
0151     inline bool operator==(const QJsonValue &other) const { return concrete(*this) == other; }
0152     inline bool operator!=(const QJsonValue &other) const { return concrete(*this) != other; }
0153
0154 protected:
0155     Q_CORE_EXPORT static QJsonValue::Type
0156     concreteType(QJsonValueConstRef self) noexcept Q_DECL_PURE_FUNCTION;
0157     Q_CORE_EXPORT static bool
0158     concreteBool(QJsonValueConstRef self, bool defaultValue) noexcept Q_DECL_PURE_FUNCTION;
0159     Q_CORE_EXPORT static qint64
0160     concreteInt(QJsonValueConstRef self, qint64 defaultValue, bool clamp) noexcept Q_DECL_PURE_FUNCTION;
0161     Q_CORE_EXPORT static double
0162     concreteDouble(QJsonValueConstRef self, double defaultValue) noexcept Q_DECL_PURE_FUNCTION;
0163     Q_CORE_EXPORT static QString concreteString(QJsonValueConstRef self, const QString &defaultValue);
0164     Q_CORE_EXPORT static QJsonValue concrete(QJsonValueConstRef self) noexcept;
0165
0166     // for iterators
0167     Q_CORE_EXPORT static QString objectKey(QJsonValueConstRef self);
0168     QString objectKey() const { return objectKey(*this); }
0169
0170 #if QT_VERSION < QT_VERSION_CHECK(7, 0, 0) && !defined(QT_BOOTSTRAPPED)
0171     QJsonValueConstRef(QJsonArray *array, qsizetype idx)
0172         : a(array), is_object(false), index(static_cast<quint64>(idx)) {}
0173     QJsonValueConstRef(QJsonObject *object, qsizetype idx)
0174         : o(object), is_object(true), index(static_cast<quint64>(idx)) {}
0175
0176     void rebind(QJsonValueConstRef other)
0177     {
0178         Q_ASSERT(is_object == other.is_object);
0179         if (is_object)
0180             o = other.o;
0181         else
0182             a = other.a;
0183         index = other.index;
0184     }
0185
0186     union {
0187         QJsonArray *a;
0188         QJsonObject *o;
0189         void *d;
0190     };
0191     quint64 is_object : 1;
0192     quint64 index : 63;
0193 #else
0194     constexpr QJsonValueConstRef(QCborContainerPrivate *d, size_t index, bool is_object)
0195         : d(d), is_object(is_object), index(index)
0196     {}
0197
0198     // implemented in qjsonarray.h & qjsonobject.h, to get their d
0199     QJsonValueConstRef(QJsonArray *array, qsizetype idx);
0200     QJsonValueConstRef(QJsonObject *object, qsizetype idx);
0201
0202     void rebind(QJsonValueConstRef other)
0203     {
0204         d = other.d;
0205         index = other.index;
0206     }
0207
0208     QCborContainerPrivate *d = nullptr;
0209     size_t is_object : 1;
0210     size_t index : std::numeric_limits<size_t>::digits - 1;
0211 #endif
0212
0213     friend class QJsonArray;
0214     friend class QJsonObject;
0215     friend class QJsonPrivate::Value;
0216 };
0217
0218 QT_WARNING_PUSH
0219 QT6_ONLY(QT_WARNING_DISABLE_MSVC(4275)) // non dll-interface class 'QJsonValueConstRef' used as base for dll-interface class 'QJsonValueRef'
0220 class QT6_ONLY(Q_CORE_EXPORT) QJsonValueRef : public QJsonValueConstRef
0221 {
0222 public:
0223     QJsonValueRef(const QJsonValueRef &) = default;
0224     QT7_ONLY(Q_CORE_EXPORT) QJsonValueRef &operator = (const QJsonValue &val);
0225     QT7_ONLY(Q_CORE_EXPORT) QJsonValueRef &operator = (const QJsonValueRef &val);
0226
0227 #if QT_VERSION < QT_VERSION_CHECK(7, 0, 0) && !defined(QT_BOOTSTRAPPED)
0228     // retained for binary compatibility (due to the Q_CORE_EXPORT) because at
0229     // least one compiler emits and exports all inlines in an exported class
0230
0231     QJsonValueRef(QJsonArray *array, qsizetype idx)
0232         : QJsonValueConstRef(array, idx) {}
0233     QJsonValueRef(QJsonObject *object, qsizetype idx)
0234         : QJsonValueConstRef(object, idx) {}
0235
0236     operator QJsonValue() const { return toValue(); }
0237
0238     QVariant toVariant() const;
0239     inline QJsonValue::Type type() const { return QJsonValueConstRef::type(); }
0240     inline bool isNull() const { return type() == QJsonValue::Null; }
0241     inline bool isBool() const { return type() == QJsonValue::Bool; }
0242     inline bool isDouble() const { return type() == QJsonValue::Double; }
0243     inline bool isString() const { return type() == QJsonValue::String; }
0244     inline bool isArray() const { return type() == QJsonValue::Array; }
0245     inline bool isObject() const { return type() == QJsonValue::Object; }
0246     inline bool isUndefined() const { return type() == QJsonValue::Undefined; }
0247
0248     inline bool toBool(bool defaultValue = false) const { return QJsonValueConstRef::toBool(defaultValue); }
0249     inline int toInt(int defaultValue = 0) const { return QJsonValueConstRef::toInt(defaultValue); }
0250     inline qint64 toInteger(qint64 defaultValue = 0) const { return QJsonValueConstRef::toInteger(defaultValue); }
0251     inline double toDouble(double defaultValue = 0) const { return QJsonValueConstRef::toDouble(defaultValue); }
0252     inline QString toString(const QString &defaultValue = {}) const { return QJsonValueConstRef::toString(defaultValue); }
0253     QJsonArray toArray() const;
0254     QJsonObject toObject() const;
0255
0256     const QJsonValue operator[](QStringView key) const { return QJsonValueConstRef::operator[](key); }
0257     const QJsonValue operator[](QLatin1StringView key) const { return QJsonValueConstRef::operator[](key); }
0258     const QJsonValue operator[](qsizetype i) const { return QJsonValueConstRef::operator[](i); }
0259
0260     inline bool operator==(const QJsonValue &other) const { return QJsonValueConstRef::operator==(other); }
0261     inline bool operator!=(const QJsonValue &other) const { return QJsonValueConstRef::operator!=(other); }
0262
0263 private:
0264     QJsonValue toValue() const;
0265 #else
0266     using QJsonValueConstRef::operator[];
0267     Q_CORE_EXPORT QJsonValueRef operator[](QAnyStringView key);
0268     Q_CORE_EXPORT QJsonValueRef operator[](qsizetype i);
0269
0270 private:
0271     using QJsonValueConstRef::QJsonValueConstRef;
0272 #endif // < Qt 7
0273
0274     QT7_ONLY(Q_CORE_EXPORT) void detach();
0275     friend class QJsonArray;
0276     friend class QJsonObject;
0277 };
0278 QT_WARNING_POP
0279
0280 inline QJsonValue QCborValueConstRef::toJsonValue() const
0281 {
0282     return concrete().toJsonValue();
0283 }
0284
0285 inline bool operator==(const QJsonValueConstRef &lhs, const QJsonValueRef &rhs)
0286 { return QJsonValue(lhs) == QJsonValue(rhs); }
0287 inline bool operator!=(const QJsonValueConstRef &lhs, const QJsonValueRef &rhs)
0288 { return !(lhs == rhs); }
0289
0290 inline bool operator==(const QJsonValueRef &lhs, const QJsonValueConstRef &rhs)
0291 { return QJsonValue(lhs) == QJsonValue(rhs); }
0292 inline bool operator!=(const QJsonValueRef &lhs, const QJsonValueConstRef &rhs)
0293 { return !(lhs == rhs); }
0294
0295 inline bool operator==(const QJsonValueRef &lhs, const QJsonValueRef &rhs)
0296 { return QJsonValue(lhs) == QJsonValue(rhs); }
0297 inline bool operator!=(const QJsonValueRef &lhs, const QJsonValueRef &rhs)
0298 { return !(lhs == rhs); }
0299
0300 Q_CORE_EXPORT size_t qHash(const QJsonValue &value, size_t seed = 0);
0301
0302 #if !defined(QT_NO_DEBUG_STREAM) && !defined(QT_JSON_READONLY)
0303 Q_CORE_EXPORT QDebug operator<<(QDebug, const QJsonValue &);
0304 #endif
0305
0306 #ifndef QT_NO_DATASTREAM
0307 Q_CORE_EXPORT QDataStream &operator<<(QDataStream &, const QJsonValue &);
0308 Q_CORE_EXPORT QDataStream &operator>>(QDataStream &, QJsonValue &);
0309 #endif
0310
0311 QT_END_NAMESPACE
0312
0313 #endif // QJSONVALUE_H