JSON has an easier grammar and is more lightweight than XML, leading to better performance. It is also readable, transportation independent, and can represent almost any data. There are parsers available for JSON in every programming language. Jackson and Gson are two libraries that can be used to parse JSON in Java - with Jackson using ObjectMapper to read/write JSON strings to POJOs, and Gson using similar fromJson/toJson methods. The POJOs need default constructors when parsing with these libraries.

1. JSON Parsing
Jackson and Gson

2. Why Json over XML
• Easier grammar
• Lightweight so better performance
• Parsers available for every language
• Better readability
• Transportation independent
• Almost any kind of data can be coded as JSON.

3. Parsing JsonUsing JACKSON
ObjectMapper mapper = new ObjectMapper();
– mapper.readValue(jsonString, targetPOJO.class);
– mapper.writeValue(jsonString, javaObject)
• POJO should have a default constructor.
JSON string POJO

4. Parsing JsonUsing Gson
Gson gson = new Gson();
– gson.fromJson(jsonString, targetPOJO.class);
– gson.toJson(javaObject)
JSON string POJO