json_builder_pro 1.0.1

A powerful and intuitive library for building and manipulating JSON structures in Dart.

JSON Builder Pro

A powerful and intuitive Dart package for programmatically building, manipulating, and serializing JSON structures using a tree-based, object-oriented approach.

Say goodbye to manual Map<String, dynamic> manipulation and complex JSON string concatenation. This package provides a robust, type-safe way to construct and modify JSON data, making it ideal for API request/response handling, configuration management, or any Dart/Flutter project that requires dynamic JSON generation.

Key Features

• 🌳 Intuitive Tree-Based Model: Represents JSON data as a logical tree of JSONElement nodes (like JSONObject, JSONArray) and leaves (like JSONString, JSONNumber, JSONBoolean, JSONNull). This makes complex JSON structures easy to manage and navigate.
• ✨ Object-Oriented API: Interact with JSON data using familiar object-oriented methods (set, get, add, remove), providing a clean and readable alternative to raw Map and List operations.
• 🔗 Parent-Aware Elements: Each JSONElement is aware of its parent, enabling powerful operations like removeMySelf() where an element can remove itself from its parent structure, simplifying complex deletion logic.
• 🚀 Pure Dart & Flutter Compatible: Written in 100% Dart, ensuring seamless integration with any Dart or Flutter project on any platform.
• 🔄 Dynamic Structure Manipulation: Easily add, update, or remove elements at any level of the JSON tree, maintaining structural integrity automatically.

Core Concept: The JSON Tree

Think of JSONTree as a structured builder for your JSON data. Instead of a flat string or a raw Map, your JSON lives in a hierarchical tree.

• JSONTree: The main class you interact with. It holds the root of your JSON structure (either a JSONObject or a JSONArray).
• JSONElement: The abstract base class for all JSON components. It provides common functionality like toJsonString() and the removeMySelf() method.
• JSONObject: Represents a JSON object ({}). It manages key-value pairs where keys are Strings and values are JSONElements.
• JSONArray: Represents a JSON array ([]). It manages an ordered list of JSONElements.
• JSONString, JSONNumber, JSONBoolean, JSONNull: These are the leaf nodes, representing the primitive JSON data types.

When you add elements to a JSONObject or JSONArray, the package automatically establishes the parent-child relationships, allowing for powerful tree traversal and manipulation.

Installation

Add this to your pubspec.yaml file:

dependencies:
  json_builder_pro: ^1.0.1 # Use the latest version

Then, run flutter pub get or dart pub get.

Getting Started

Let's build a simple JSON object: {"name":"Alice","age":30}

import 'package:json_builder/json_builder.dart';

void main() {
  // 1. Create a JSON Tree with a root object
  final tree = JSONTree(initialType: JETypes.object);
  final rootObject =
      tree.root as JSONObject; // Cast to JSONObject to use its methods

  // 2. Add primitive elements
  rootObject.set('name', JSONString('Alice'));
  rootObject.set('age', JSONNumber(30));

  print('Initial Tree: ${tree.toJsonString()}');
  // Expected: {"name":"Alice","age":30}
}

Advanced Usage

Building Nested Structures

Let's build a more complex JSON structure with nested objects and arrays:

import 'package:json_builder/json_builder.dart';

void main() {
  final tree = JSONTree(initialType: JETypes.object);
  final rootObject = tree.root as JSONObject;

  rootObject.set('name', JSONString('Alice'));
  rootObject.set('age', JSONNumber(30));

  // Add an array of hobbies
  final hobbies = JSONArray();
  hobbies.add(JSONString('reading'));
  hobbies.add(JSONString('coding'));
  rootObject.set('hobbies', hobbies);

  // Add a nested contact object
  final contact = JSONObject();
  contact.set('email', JSONString('[e-mail]'));
  contact.set('phone', JSONString('123-456-7890'));
  rootObject.set('contact', contact);

  print('Complex Tree: ${tree.toJsonString()}');
  // Expected: {"name":"Alice","age":30,"hobbies":["reading","coding"],"contact":{"email":"[e-mail]","phone":"123-456-7890"}}
}

Using removeMySelf()

The removeMySelf() method allows any JSONElement to remove itself from its parent, simplifying deletion logic, especially in complex, deeply nested structures.

import 'package:json_builder/json_builder.dart';

void main() {
  final tree = JSONTree(initialType: JETypes.object);
  final rootObject = tree.root as JSONObject;

  rootObject.set('name', JSONString('Alice'));
  rootObject.set('age', JSONNumber(30));

  final hobbies = JSONArray();
  hobbies.add(JSONString('reading'));
  hobbies.add(JSONString('coding'));
  rootObject.set('hobbies', hobbies);

  // Get a reference to the 'age' element
  final ageElement = rootObject.get('age');
  print('Tree before removal: ${tree.toJsonString()}');

  // Remove 'age' using removeMySelf()
  final wasRemoved = ageElement?.removeMySelf();
  print('Age element removed: $wasRemoved'); // Should be true
  print('Tree after removal: ${tree.toJsonString()}');
  // Expected: {"name":"Alice","hobbies":["reading","coding"]}

  // Get a reference to 'coding' from the hobbies array
  final codingElement = (hobbies.elements[1] as JSONString);
  print('Tree before removing coding: ${tree.toJsonString()}');

  // Remove 'coding' using removeMySelf()
  final wasCodingRemoved = codingElement.removeMySelf();
  print('Coding element removed: $wasCodingRemoved'); // Should be true
  print('Tree after removing coding: ${tree.toJsonString()}');
  // Expected: {"name":"Alice","hobbies":["reading"]}
}

API Reference

• JSONTree: The main entry point for building a JSON structure.

  • JSONTree({required JETypes initialType}): Constructor to initialize the tree with a root object or array.
  • JSONElement get root: Gets the root JSONElement of the tree.
  • String toJsonString(): Converts the entire tree to its JSON string representation.

• JSONElement: Abstract base class for all JSON types.

  • String get getType: Returns the type of the JSON element (e.g., 'object', 'array', 'string').
  • String toJsonString(): Converts the element to its JSON string representation.
  • bool removeMySelf(): Attempts to remove this element from its parent. Returns true if successful.

• JSONObject: Represents a JSON object.

  • JSONObject([Map<String, JSONElement>? initialMembers, ParentRemover? parentRemover]): Constructor.
  • Map<String, JSONElement> get members: Gets the underlying map of members.
  • void set(String key, JSONElement value): Adds or updates a key-value pair.
  • JSONElement? get(String key): Retrieves an element by key.
  • JSONElement? remove(String key): Removes a key-value pair and returns the removed element.
  • bool containsKey(String key): Checks if the object contains a key.
  • void clear(): Removes all members.

• JSONArray: Represents a JSON array.

  • JSONArray([List<JSONElement>? initialElements, ParentRemover? parentRemover]): Constructor.
  • List<JSONElement> get elements: Gets the underlying list of elements.
  • void add(JSONElement element): Adds an element to the end.
  • void addAll(Iterable<JSONElement> newElements): Adds multiple elements.
  • void insert(int index, JSONElement newElement): Inserts an element at a specific index.
  • bool remove(JSONElement element): Removes the first occurrence of an element.
  • JSONElement removeAt(int index): Removes an element at a specific index.
  • void clear(): Removes all elements.

• JSONString, JSONNumber, JSONBoolean, JSONNull: Concrete implementations of JSONElement for primitive types.

  • Each has a value property (except JSONNull).

• JETypes: An enum representing all possible JSON element types.

Contributing

Contributions are welcome! If you find a bug or have a feature request, please file an issue on the issue tracker. If you want to contribute code, please feel free to open a pull request on the repository.

License

This package is licensed under the MIT License.