J4Json - JSON Library in Java

A Java JSON builder - parser library.

Synopsis

J4Json is a simple Java library for generating / parsing JSON. It provides a simple and yet flexible API.

Getting Started

If you use Maven, you can (locally) build and install the j4json library using standard Maven goals. (If you don't use Maven, then there is an ant script under nomaven/scripts.) Otherwise, you can add, in your project, the following dependency:

<dependency>
  <groupId>org.j4json</groupId>
  <artifactId>j4json-core</artifactId>
  <version>0.9.2</version>
</dependency>

J4Json is compatible with JDK 1.7 or later.

High Level API Design

J4Json provides the basic JSON APIs for parse() and build(). In addition, J4Json provides two extra sets of APIs, which differentiate itself from other JSON libraries.

Configurable Parsing/Building

J4Json includes certain Builder (JSON generator) and Parser classes which take "policy" objects as inputs. These policy objects can be used to customize the parsing/building operations.

"Partial" Parsing/Building

This is rather unique to J4Json. All JSON parsers and JSON generators/builders implement parsing/building as all-or-none operations. Given a JSON string, a parser creates an object corresponding to the JSON string. Given an object, a builder generates a JSON string representation of the object.

On the other hand, J4Json includes APIs which can do "partial parsing" or "partial building".

API

High Level APIs

At the highest/simplest level, simple wrapper classes, MiniJsonParser and MiniJsonBuilder, can be used to parse/build JSON.

JsonParser miniParser = new MiniJsonParser();
String json = "{\"a\":\"b\"}";
Object obj = miniParser.parse(json);

JsonBuilder miniBuilder = new MiniJsonBuilder();
Object obj = ...;
String json = miniBuilder.build(obj, 4);

Alternatively, high-level JSON Object/Array wrappers, MiniJsonObject and MiniJsonArray, can be used to parse/build JSON.

Map<String,Object> obj1 = ...;
JsonObject miniObject1 = new MiniJsonObject(obj1);
String json1 = miniObject1.toJsonString();

String json2 = ...;
JsonObject miniObject2 = new MiniJsonObject(json2);
Object obj2 = miniObject2.toJsonStructure();

Full Parser/Builder APIs

(TBD)

"Partial" Parser/Builder APIs

(TBD)

Please refer to the online API Docs for more information.