Java JSON Tutorial

Java JSON Tutorial

Posted on August 12, 2011 ,     Last modified : August 23, 2011
By
mkyong





JSON (JavaScript Object Notation), is a simple and easy to read and write data exchange format. It’s popular and implemented in countless projects worldwide, for those don’t like XML, JSON is a very good alternative solution.

In this series of Java JSON tutorials, we focus on three popular third party Java libraries to process JSON data, which are
Jackson, Google Gson and JSON.simple

Jackson

A High-performance JSON processor.

Jackson data binding example – Object & JSON

Example to use ObjectMapper writeValue() and readValue() to convert Java object to / from JSON.
Jackson data binding example – Map & JSON

Example to convert Java Map to / from JSON
Jackson Tree Model example

Read JSON into Tree, like DOM for XML.
Jackson Streaming example

Example to use JsonGenerator() and JsonParser() to stream read and write JSON data.
Pretty print JSON output in Jackson

Pretty print JSON output via defaultPrettyPrintingWriter().

Google Gson

It was originally created for use inside Google, now it is used by many
public projects.

Gson data model example – Object & JSON

Example to use toJson() and fromJson() to convert Java Object to / from JSON.
Gson Streaming example

Example to use JsonWriter() and JsonReader () to stream read and write JSON data.
Pretty print JSON output in Gson

Pretty print JSON output via GsonBuilder.

JSON.simple

Simple Java library for JSON, to read and write JSON data.

JSON.simple example – Read and write JSON

Example to show you how to read and write JSON data to / from file.

References

Introducing JSON
JSON described in RFC 4627
JSON Wiki
Jackson official website
Gson official website
JSON.simple official website
Review of 5 Java JSON libraries
Jackson vs Gson