CT0442-JsonParserProject

This repository is related to the University course CT0442: "Programming and laboratory". A basic requirement to pass the course was to do a project assigned by the professor in the specifications he presented to us.

This project provides a JSON parser implemented in C++ using the following files:

• json.hpp: Header file containing the json class definition and related functions.
• json.cpp: Source file containing the implementation of the json class and related functions.

Description

The JSON parser is designed to parse and manipulate JSON data in C++. It provides a json class with various methods for handling different JSON data types, such as null, boolean, number, string, list, and dictionary.

Features

json.cpp contains the implementation of the json class methods and operators defined in json.hpp. It includes functions for:

• Parsing JSON data from a JSON file.
• Outputting JSON data to a JSON file.
• Handling different JSON data types (null, boolean, number, string, list, and dictionary).

Structure

The json.cpp file is organized as follows:

1. Implementation of the json class methods, such as is_list, is_dictionary, is_string, is_number, is_bool, and is_null.
2. Accessors and modifiers for JSON data, such as get_number, get_bool, get_string, set_string, set_bool, set_number, set_null, set_list, and set_dictionary.
3. Iterators for lists and dictionaries, such as begin_list, end_list, begin_dictionary, and end_dictionary.
4. Overloaded input and output stream operators for reading and writing JSON data.

Parse

The parse function in json.cpp takes a string as input and returns a json object [1]. It checks the input string for different JSON data types (such as lists, dictionaries, strings, numbers, booleans, and null values) and sets the corresponding value in the json object. The function uses a series of conditional statements and loops to identify and process each JSON data type.

For example, when parsing a list, the function iterates through the input string and checks for opening and closing brackets, as well as nested lists and dictionaries. If the input string is not well-formed (e.g., a list is not closed or a string is not enclosed in double quotes), the function throws a json_exception with a specific error message.

Exceptions for Debugging

The json_exception struct is defined in json.hpp and is used to throw exceptions when an error occurs during parsing or other operations. The json_exception struct contains a msg field, which is a string that stores the error message. This exception can be used to debug the code or the input files by providing more information about the error encountered.

For instance, when the parse function encounters an ill-formed list or dictionary, it throws a json_exception with a message indicating the specific issue, such as "La lista non è ben formata - Dizionario non chiuso - parse" or "La lista non è ben formata - Stringa non chiusa - parse". By catching and handling these exceptions in your code, you can identify and fix issues with the input JSON data or the parser implementation.