Essential Json

JSON without fuss

Description

Although there are already tons of existing Java JSON libraries, here is one which: + is minimalistic (no validation, no schema, no custom POJO field/class support) + has no external dependency + is easily pluggable in other projects: one single source file + is performant + has a nice and handy API with specialized getters + avoids any kind of abstraction other than Serializable around values, without any wrapping + uses a common parent Serializable interface for JSON objects and arrays

Programming language: Java

License: Apache License 2.0

Tags: JSON     Serialization     Parsing    

Latest version: v2.6.2

README

Essential JSON

• Essential JSON
  • Rationale
  • Description
  • Usage
  • Inclusion in your project
  • Parsing JSON
  • Rendering JSON
  • Building JSON
  • Converting to JSON
  • References

Rationale

Although there are already tons of existing Java JSON libraries, I needed one which would:

• be minimalistic

  • no reflection of any sort, no validation, no schema, no custom POJO field/class support
  • no external dependency
  • easily pluggable in other projects: one single source file

• be performant

• have a nice and handy API with specialized getters and setters

• avoid any kind of abstraction other than Serializable around values, without any wrapping

• use a common parent Serializable interface for JSON objects and arrays

Description

Usage

The com.republicate.json.Json interface extends Serializable and is implemented by its two inner classes Json.Array and Json.Object.

Json.Array extends List<Serializable> and Json.Object extends Map<String, Serializable>.

Inclusion in your project

Using Maven:

<dependency>
    <groupId>com.republicate</groupId>
    <artifactId>essential-json</artifactId>
    <version>2.5</version>
</dependency>

Using Gradle:

implementation 'com.republicate:essential-json:2.3'

Parsing JSON

The generic Json.parse(string_or_reader) method will return a com.republicate.Json value containing a Json.Object or Json.Array object.

If you want to parse a content without knowing if it's a JSON container or a simple JSON value, you will call the Json.parseValue(string_or_reader) method to get a Serializable.

import com.republicate.json.Json;
...
Json container = Json.parse(string_or_reader);
// container will be a JSON object or a JSON array
if (container.isObject())
{
    Json.Object obj = container.asObject();
    ...
}

Serializable value = Json.parseValue(string_or_reader);
// value will either be a JSON container or a single Serializable value

Rendering JSON

Containers toString() and toString(Writer) methods will render JSON strings with proper quoting and encoding.

import com.republicate.json.Json;
...
// getting a String
String json = container.toString();

// rendering towards a Writer
container.toString(writer);

Building JSON

Json.Array and Json.Object constructors (or equivalents Json.newArray() and Json.newObject() helper methods) can respectively be given an existing Iterable or an existing Map ; both can also be given a JSON string.

Both containers have specialized getters (getString, getBoolean, etc.).

Json.Array has helper methods push, pushAll and put that return self (and rely on the standard add, addAll and set ArrayList methods).

Json.Object has helper methods set and setAll that return self (and rely on the standard put and putAll Map methods).

import com.republicate.json.Json;
...
Json.Array arr = Json.newArray("[1,2,3]").add(4).add(5);
Json.Object obj = new Json.Object(some_existing_map).set("foo", "bar").set(("baz", arr);

Converting to JSON

The two reentrant methods Json.toJson(java.lang.Object) and Json.toSerializable(java.lang.Object) will try hard to convert any standard Java container to a JSON structure.

References

• RFC 7159
• JSON Parsing Test Suite