Gson is a Java library that can be used to convert Java Objects into their JSON representation. It can also be used to convert a JSON string to an equivalent Java object. Gson can work with arbitrary Java objects including pre-existing objects that you do not have source-code of.
There are a few open-source projects that can convert Java objects to JSON. However, most of them require that you place Java annotations in your classes; something that you can not do if you do not have access to the source-code. Most also do not fully support the use of Java Generics. Gson considers both of these as very important design goals.
Gson Goals
- Provide simple
toJson()andfromJson()methods to convert Java objects to JSON and vice-versa - Allow pre-existing unmodifiable objects to be converted to and from JSON
- Extensive support of Java Generics
- Allow custom representations for objects
- Support arbitrarily complex objects (with deep inheritance hierarchies and extensive use of generic types)
Gson Downloads
- Gson 2.5 Download downloads at Maven Central
Gson Documentation
- Gson API: Javadocs for the current Gson release
- Gson user guide: This guide contains examples on how to use Gson in your code.
- Gson Roadmap: Details of changes in the recent versions
- Gson design document: This document discusses issues we faced while designing Gson. It also include a comparison of Gson with other Java libraries that can be used for Json conversion
Please use the google-gson Google group to discuss Gson, or to post questions.
Gson-related Content Created by Third Parties
- Gson Tutorial by
StudyTrails
License
Gson is released under the Apache 2.0 license.
Copyright 2008 Google Inc.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.