#if !defined(JANSSONXX_H) #define JANSSONXX_H 1 #include namespace jansson { // include in the jansson namespace #include class Iterator; // represents any JSON value class Value { public: // construct new Value with an undefined value Value() : _value(0) {} // free Value resources ~Value() { json_decref(_value); } // copy an existing Value Value(const Value& e) : _value(json_incref(e._value)) {} // make a reference to an existing json_t value explicit Value(json_t* value) : _value(json_incref(value)) {} // copy an existing Value Value& operator=(const Value& e) { json_decref(_value); _value = json_incref(e._value); return *this; } // take ownership of a json_t (does not increase reference count) Value& take_ownership(json_t* value) { json_decref(_value); _value = value; return *this; } // load a file as a JSON value static Value load_file(const char* path, json_error_t* error = 0) { return Value().take_ownership(json_load_file(path, error)); } // load a string as a JSON value static Value load_string(const char* string, json_error_t* error = 0) { return Value().take_ownership(json_loads(string, error)); } // write the value to a file int save_file(const char* path, int flags = JSON_INDENT(2)) const { return json_dump_file(_value, path, flags); } // write the value to a string (caller must deallocate with free()!) char* save_string(int flags = JSON_INDENT(2)) const { return json_dumps(_value, flags); } // construct Value from input static Value from(const char* value) { return Value().take_ownership(json_string(value)); } static Value from(const std::string& value) { return from(value.c_str()); } static Value from(bool value) { return Value().take_ownership(value ? json_true() : json_false()); } static Value from(int value) { return Value().take_ownership(json_integer(value)); } static Value from(double value) { return Value().take_ownership(json_real(value)); } // create a new empty object static Value object() { return Value().take_ownership(json_object()); } // create a new empty array static Value array() { return Value().take_ownership(json_array()); } // create a new null value static Value null() { return Value().take_ownership(json_null()); } // get the underlying json_t json_t* as_json_t() const { return _value; } // check value type bool is_undefined() const { return _value == 0; } bool is_object() const { return json_is_object(_value); } bool is_array() const { return json_is_array(_value); } bool is_string() const { return json_is_string(_value); } bool is_integer() const { return json_is_integer(_value); } bool is_real() const { return json_is_real(_value); } bool is_number() const { return json_is_number(_value); } bool is_true() const { return json_is_true(_value); } bool is_false() const { return json_is_false(_value); } bool is_boolean() const { return json_is_boolean(_value); } bool is_null() const { return json_is_null(_value); } // get size of array or object unsigned int size() const { if (is_object()) return json_object_size(_value); else if (is_array()) return json_array_size(_value); else return 0; } // get value at array index (const version) const Value at(unsigned int index) const { if (is_array()) return Value(json_array_get(_value, index)); else return Value(); } const Value operator[](signed int index) const { return at(index); } const Value operator[](unsigned int index) const { return at(index); } const Value operator[](signed short index) const { return at(index); } const Value operator[](unsigned short index) const { return at(index); } const Value operator[](signed long index) const { return at(index); } const Value operator[](unsigned long index) const { return at(index); } // get value at array index (non-const version) Value at(unsigned int index) { if (is_array()) return Value(json_array_get(_value, index)); else return Value(); } Value operator[](signed int index) { return at(index); } Value operator[](unsigned int index) { return at(index); } Value operator[](signed short index) { return at(index); } Value operator[](unsigned short index) { return at(index); } Value operator[](signed long index) { return at(index); } Value operator[](unsigned long index) { return at(index); } // get object property const Value get(const char* key) const { if (is_object()) return Value(json_object_get(_value, key)); else return Value(); } const Value get(const std::string& key) const { return get(key.c_str()); } const Value operator[](const char* key) const { return get(key); } const Value operator[](const std::string& key) const { return get(key.c_str()); } // clear all array/object values void clear() { if (is_object()) json_object_clear(_value); else if (is_array()) json_array_clear(_value); } // get value cast to specified type const char* as_cstring() const { return json_string_value(_value); } std::string as_string() const { return as_cstring(); } int as_integer() const { return json_integer_value(_value); } double as_real() const { return json_real_value(_value); } double as_number() const { return json_number_value(_value); } bool as_boolean() const { return is_true(); } // set an object property (converts value to object is not one already) Value& set(const char* key, const Value& value) { if (!is_object()) { json_decref(_value); _value = json_object(); } json_object_set(_value, key, value.as_json_t()); return *this; } // set an array index (converts value to object is not one already) Value& set(unsigned int index, const Value& value) { if (!is_array()) { json_decref(_value); _value = json_array(); } if (index == size()) json_array_append(_value, value.as_json_t()); else json_array_set(_value, index, value.as_json_t()); return *this; } Value& set(int index, const Value& value) { return set(static_cast(index), value); } private: // internal value pointer json_t* _value; }; // iterators over a JSON object class Iterator { public: // construct a new iterator for a given object Iterator(const Value& value) : _object(value), _iter(0) { _iter = json_object_iter(_object.as_json_t()); } // increment iterator void next() { if (_iter != 0) _iter = json_object_iter_next(_object.as_json_t(), _iter); } Iterator& operator++() { next(); return *this; } // test if iterator is still valid bool valid() const { return _iter != 0; } operator bool() const { return valid(); } // get key const char* ckey() const { if (_iter != 0) return json_object_iter_key(_iter); else return ""; } std::string key() const { return ckey(); } // get value const Value value() const { if (_iter != 0) return Value(json_object_iter_value(_iter)); else return Value(); } // dereference value const Value operator*() const { return value(); } private: // disallow copying Iterator(const Iterator&); Iterator& operator=(const Iterator&); // object being iterated over Value _object; // iterator value void* _iter; }; } // namespace jansson #endif