nlohmann::detail::json_sax_dom_parser< BasicJsonType > Class Template Reference

SAX implementation to create a JSON value from SAX events. More...

#include <json.hpp>

Public Types
using	number_integer_t = typename BasicJsonType::number_integer_t
using	number_unsigned_t = typename BasicJsonType::number_unsigned_t
using	number_float_t = typename BasicJsonType::number_float_t
using	string_t = typename BasicJsonType::string_t

Public Member Functions
	json_sax_dom_parser (BasicJsonType &r, const bool allow_exceptions_=true)
	json_sax_dom_parser (const json_sax_dom_parser &)=delete
	json_sax_dom_parser (json_sax_dom_parser &&)=default
json_sax_dom_parser &	operator= (const json_sax_dom_parser &)=delete
json_sax_dom_parser &	operator= (json_sax_dom_parser &&)=default
	~json_sax_dom_parser ()=default
bool	null ()
bool	boolean (bool val)
bool	number_integer (number_integer_t val)
bool	number_unsigned (number_unsigned_t val)
bool	number_float (number_float_t val, const string_t &)
bool	string (string_t &val)
bool	start_object (std::size_t len)
bool	key (string_t &val)
bool	end_object ()
bool	start_array (std::size_t len)
bool	end_array ()
bool	parse_error (std::size_t, const std::string &, const detail::exception &ex)
constexpr bool	is_errored () const

Private Member Functions
template<typename Value >
JSON_HEDLEY_RETURNS_NON_NULL BasicJsonType *	handle_value (Value &&v)

Private Attributes
BasicJsonType &	root
	the parsed JSON value More...
std::vector< BasicJsonType * >	ref_stack {}
	stack to model hierarchy of values More...
BasicJsonType *	object_element = nullptr
	helper to hold the reference for the next object element More...
bool	errored = false
	whether a syntax error occurred More...
const bool	allow_exceptions = true
	whether to throw exceptions in case of errors More...

Detailed Description

template<typename BasicJsonType>
class nlohmann::detail::json_sax_dom_parser< BasicJsonType >

SAX implementation to create a JSON value from SAX events.

This class implements the json_sax interface and processes the SAX events to create a JSON value which makes it basically a DOM parser. The structure or hierarchy of the JSON value is managed by the stack ref_stack which contains a pointer to the respective array or object for each recursion depth.

After successful parsing, the value that is passed by reference to the constructor contains the parsed value.

Template Parameters

BasicJsonType

the JSON type

Definition at line 4454 of file json.hpp.

Member Typedef Documentation

template<typename BasicJsonType>

using nlohmann::detail::json_sax_dom_parser< BasicJsonType >::number_float_t = typename BasicJsonType::number_float_t

Definition at line 4459 of file json.hpp.

template<typename BasicJsonType>

using nlohmann::detail::json_sax_dom_parser< BasicJsonType >::number_integer_t = typename BasicJsonType::number_integer_t

Definition at line 4457 of file json.hpp.

template<typename BasicJsonType>

using nlohmann::detail::json_sax_dom_parser< BasicJsonType >::number_unsigned_t = typename BasicJsonType::number_unsigned_t

Definition at line 4458 of file json.hpp.

template<typename BasicJsonType>

using nlohmann::detail::json_sax_dom_parser< BasicJsonType >::string_t = typename BasicJsonType::string_t

Definition at line 4460 of file json.hpp.

Constructor & Destructor Documentation

template<typename BasicJsonType>

nlohmann::detail::json_sax_dom_parser< BasicJsonType >::json_sax_dom_parser ( BasicJsonType &  r, const bool  allow_exceptions_ = true  )

inlineexplicit

Parameters

[in,out]	r	reference to a JSON value that is manipulated while parsing
[in]	allow_exceptions_	whether parse errors yield exceptions

Definition at line 4467 of file json.hpp.

        : root(r), allow_exceptions(allow_exceptions_)
    {}

template<typename BasicJsonType>

nlohmann::detail::json_sax_dom_parser< BasicJsonType >::json_sax_dom_parser ( const json_sax_dom_parser< BasicJsonType > &  )

delete

template<typename BasicJsonType>

nlohmann::detail::json_sax_dom_parser< BasicJsonType >::json_sax_dom_parser ( json_sax_dom_parser< BasicJsonType > &&  )

default

template<typename BasicJsonType>

nlohmann::detail::json_sax_dom_parser< BasicJsonType >::~json_sax_dom_parser ( )

default

Member Function Documentation

template<typename BasicJsonType>

bool nlohmann::detail::json_sax_dom_parser< BasicJsonType >::boolean ( bool  val )

inline

Definition at line 4484 of file json.hpp.

    {
        handle_value(val);
        return true;
    }

template<typename BasicJsonType>

bool nlohmann::detail::json_sax_dom_parser< BasicJsonType >::end_array ( )

inline

Definition at line 4553 of file json.hpp.

    {
        ref_stack.pop_back();
        return true;
    }

template<typename BasicJsonType>

bool nlohmann::detail::json_sax_dom_parser< BasicJsonType >::end_object ( )

inline

Definition at line 4534 of file json.hpp.

    {
        ref_stack.pop_back();
        return true;
    }

template<typename BasicJsonType>

template<typename Value >

JSON_HEDLEY_RETURNS_NON_NULL BasicJsonType* nlohmann::detail::json_sax_dom_parser< BasicJsonType >::handle_value ( Value &&  v )

inlineprivate

Invariant

If the ref stack is empty, then the passed value will be the new root.

If the ref stack contains a value, then it is an array or an object to which we can add elements

Definition at line 4601 of file json.hpp.

    {
        if (ref_stack.empty())
        {
            root = BasicJsonType(std::forward<Value>(v));
            return &root;
        }

        assert(ref_stack.back()->is_array() or ref_stack.back()->is_object());

        if (ref_stack.back()->is_array())
        {
            ref_stack.back()->m_value.array->emplace_back(std::forward<Value>(v));
            return &(ref_stack.back()->m_value.array->back());
        }

        assert(ref_stack.back()->is_object());
        assert(object_element);
        *object_element = BasicJsonType(std::forward<Value>(v));
        return object_element;
    }

template<typename BasicJsonType>

constexpr bool nlohmann::detail::json_sax_dom_parser< BasicJsonType >::is_errored ( ) const

inline

Definition at line 4587 of file json.hpp.

    {
        return errored;
    }

template<typename BasicJsonType>

bool nlohmann::detail::json_sax_dom_parser< BasicJsonType >::key ( string_t &  val )

inline

Definition at line 4527 of file json.hpp.

    {
        // add null at given key and store the reference for later
        object_element = &(ref_stack.back()->m_value.object->operator[](val));
        return true;
    }

template<typename BasicJsonType>

bool nlohmann::detail::json_sax_dom_parser< BasicJsonType >::null ( )

inline

Definition at line 4478 of file json.hpp.

    {
        handle_value(nullptr);
        return true;
    }

template<typename BasicJsonType>

bool nlohmann::detail::json_sax_dom_parser< BasicJsonType >::number_float ( number_float_t  val, const string_t &    )

inline

Definition at line 4502 of file json.hpp.

    {
        handle_value(val);
        return true;
    }

template<typename BasicJsonType>

bool nlohmann::detail::json_sax_dom_parser< BasicJsonType >::number_integer ( number_integer_t  val )

inline

Definition at line 4490 of file json.hpp.

    {
        handle_value(val);
        return true;
    }

template<typename BasicJsonType>

bool nlohmann::detail::json_sax_dom_parser< BasicJsonType >::number_unsigned ( number_unsigned_t  val )

inline

Definition at line 4496 of file json.hpp.

    {
        handle_value(val);
        return true;
    }

template<typename BasicJsonType>

json_sax_dom_parser& nlohmann::detail::json_sax_dom_parser< BasicJsonType >::operator= ( const json_sax_dom_parser< BasicJsonType > &  )

delete

template<typename BasicJsonType>

json_sax_dom_parser& nlohmann::detail::json_sax_dom_parser< BasicJsonType >::operator= ( json_sax_dom_parser< BasicJsonType > &&  )

default

template<typename BasicJsonType>

bool nlohmann::detail::json_sax_dom_parser< BasicJsonType >::parse_error ( std::size_t  , const std::string &  , const detail::exception &  ex  )

inline

Definition at line 4559 of file json.hpp.

    {
        errored = true;
        if (allow_exceptions)
        {
            // determine the proper exception type from the id
            switch ((ex.id / 100) % 100)
            {
                case 1:
                    JSON_THROW(*static_cast<const detail::parse_error*>(&ex));
                case 4:
                    JSON_THROW(*static_cast<const detail::out_of_range*>(&ex));
                // LCOV_EXCL_START
                case 2:
                    JSON_THROW(*static_cast<const detail::invalid_iterator*>(&ex));
                case 3:
                    JSON_THROW(*static_cast<const detail::type_error*>(&ex));
                case 5:
                    JSON_THROW(*static_cast<const detail::other_error*>(&ex));
                default:
                    assert(false);
                    // LCOV_EXCL_STOP
            }
        }
        return false;
    }

template<typename BasicJsonType>

bool nlohmann::detail::json_sax_dom_parser< BasicJsonType >::start_array ( std::size_t  len )

inline

Definition at line 4540 of file json.hpp.

    {
        ref_stack.push_back(handle_value(BasicJsonType::value_t::array));

        if (JSON_HEDLEY_UNLIKELY(len != std::size_t(-1) and len > ref_stack.back()->max_size()))
        {
            JSON_THROW(out_of_range::create(408,
                                            "excessive array size: " + std::to_string(len)));
        }

        return true;
    }

template<typename BasicJsonType>

bool nlohmann::detail::json_sax_dom_parser< BasicJsonType >::start_object ( std::size_t  len )

inline

Definition at line 4514 of file json.hpp.

    {
        ref_stack.push_back(handle_value(BasicJsonType::value_t::object));

        if (JSON_HEDLEY_UNLIKELY(len != std::size_t(-1) and len > ref_stack.back()->max_size()))
        {
            JSON_THROW(out_of_range::create(408,
                                            "excessive object size: " + std::to_string(len)));
        }

        return true;
    }

template<typename BasicJsonType>

bool nlohmann::detail::json_sax_dom_parser< BasicJsonType >::string ( string_t &  val )

inline

Definition at line 4508 of file json.hpp.

    {
        handle_value(val);
        return true;
    }

Member Data Documentation

template<typename BasicJsonType>

const bool nlohmann::detail::json_sax_dom_parser< BasicJsonType >::allow_exceptions = true

private

whether to throw exceptions in case of errors

Definition at line 4632 of file json.hpp.

template<typename BasicJsonType>

bool nlohmann::detail::json_sax_dom_parser< BasicJsonType >::errored = false

private

whether a syntax error occurred

Definition at line 4630 of file json.hpp.

template<typename BasicJsonType>

BasicJsonType* nlohmann::detail::json_sax_dom_parser< BasicJsonType >::object_element = nullptr

private

helper to hold the reference for the next object element

Definition at line 4628 of file json.hpp.

template<typename BasicJsonType>

std::vector<BasicJsonType*> nlohmann::detail::json_sax_dom_parser< BasicJsonType >::ref_stack {}

private

stack to model hierarchy of values

Definition at line 4626 of file json.hpp.

template<typename BasicJsonType>

BasicJsonType& nlohmann::detail::json_sax_dom_parser< BasicJsonType >::root

private

the parsed JSON value

Definition at line 4624 of file json.hpp.

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The documentation for this class was generated from the following file:

• json.hpp