JSON parsing process

Introduction to JSON

The full name of JSON is JavaScript Object Notaion. It is a lightweight data exchange format with good readability and fast writing characteristics. In terms of text, it uses highly compatible text. The usage rate in the daily process is as high as 99%,

Data types supported by JSON

1. Integer or floating point number;
2. Boolean value (true, false);
3. String
4. Array
5. function;
6. Object
7. null。

JSON basic syntax

• Object class

Use {} to contain key: Value key-value pairs, where Key and Value are separated by colons, and each key-value is separated by commas.
"Key1": "Value1", "Key2": "Value2"

• Array array class

Use [] to include all elements, each element is separated by a comma, the element can be any value
String arr1 = ["steamed bun", "winter melon", "eggplant",1,2,3]

• Combination

String arr2 = { "name" = "steamed bun", "name" = "winter melon", "eggplant" = {[1,2,3], [3,4,5]} }

JSON data analysis

Use json to convert

		Book book = new Book("102","围城","讲述了一代人的爱恨情仇");
        String json = JSON.toJSONString(book);
        System.out.println(json);

Output value: {"id":"102","info":"tells the love and hatred of a generation","name":"siege"}

1. Analysis of Object Object

		Book book = JSON.parseObject("{\"id\":\"102\",\"info\":\"讲述了一代人的爱恨情仇\",\"name\":\"围城\"}",Book.class);
        System.out.println(book.getId());
        System.out.println(book.getName());
        System.out.println(book.getInfo());

The output value is:
102
Siege
tells about the love and hatred of a generation

2. Array analysis

		List<String> list = JSON.parseArray("[\"馒头\",\"茄子\"]",String.class);
        System.out.println(list.get(0));
        System.out.println(list.get(1));

The output value is:
steamed buns
eggplant