JSON

Introduction

The OpenJAX JSON library provides JsonReader and JsonParser.

JsonReader

The JsonReader is a subclass of Reader that reads JSON documents and validates the content conforms to the RFC 4627 specification. In addition to the standard "read" methods defined in Reader, the JsonReader provides the following patterns:

1. Standard reading of "JSON tokens":
   1. Via JsonReader#readToken(), which returns tokens as Strings.
2. Iterator reading of "JSON tokens". The JsonReader implements the Iterable interface:
   1. Via Iterator#next(), which returns tokens as Strings.
3. Optimized reading of "JSON tokens":
   1. JsonReader#readTokenStart(), which returns the start index of the token.
4. Partial reading of "JSON tokens":
   1. Via: Reader#read().
   2. Via: Reader#read(char[]).
   3. Via: Reader#read(char[], int, int).
5. The JsonReader is a ReplayReader, which allows a JSON document to be re-read:
   1. Via: JsonReader#setPosition(int): The character position to be reset to previous point in the stream being read.
   2. Via: JsonReader#setIndex(int): The token index position to be reset to a previous point of enumerated "JSON tokens".
6. Ignore or preserve inter-token whitespace.
7. Unescapes string-literal JSON escape codes as defined in RFC 4627, Section 2.5.

JsonParser

The JsonParser is a validating parser for JSON documents that asserts content conforms to the RFC 4627 specification. The JsonParser is designed with performance in mind, and utilizes the JsonReader#readTokenStart() method to avoid instantiation of String object. The JsonParser accepts a JsonHandler that defines methods for the reconstitution of "JSON tokens" from the provided _start and end token indices.

JSON Tokens

JSON Tokens
Structural
A character that is one of:	[{}\[\]:,]
A property key
A string that matches:	^".*"$
A property or array member value
A string that matches:	^".*"$
A number that matches:	^-?(([0-9])|([1-9][0-9]+))(\.[\.0-9]+)? ([eE][+-]?(([0-9])|([1-9][0-9]+)))?$
A literal that matches:	^(null)|(true)|(false)$
Whitespace
Whitespace string that matches:	^[ \n\r\t]+$

Contributing

Pull requests are welcome. For major changes, please open an issue first to discuss what you would like to change.

Please make sure to update tests as appropriate.

License

This project is licensed under the MIT License - see the LICENSE.txt file for details.