What are the main functions of fastjson?

Fastjson is a JSON parsing library written in the Java language, its main functions include:

1. JSON serialization and deserialization: Java objects can be converted into strings in JSON format, and JSON strings can be converted back into Java objects.
2. Support for complex data types: can handle various complex Java data types, such as Maps, Lists, arrays, etc.
3. High performance: Fastjson has implemented a series of optimization measures, such as utilizing reflection caching, bitwise operations, etc., to make the parsing speed faster.
4. Support custom serialization and deserialization: JSON serialization and deserialization rules can be customized through annotations and interfaces.
5. Support for Java generics: it can correctly handle Java objects that contain generics.
6. Support for date and time conversion: Java’s date and time types can be converted into a JSON string of a specified format.
7. Support cycle reference detection: able to detect and handle cyclic references between Java objects.
8. Support for converting nested properties of a JSON string into a JavaBean object.
9. Support for formatting JSON strings to make them easier to view and debug.
10. Support the conversion between JSON and Java objects.
11. Support automatic type conversion: JSON strings can be automatically converted into corresponding data types in Java.

In conclusion, Fastjson is a powerful, flexible, and easy-to-use JSON parsing library widely used in Java development.