1.各种json工具包比较

四个JSON类库分别为：Gson，FastJson，Jackson，Json-lib。 

适用：使用FastJson进行JSON字符串解析，Jackson将集合转成JSON格式字符串。 

参考：https://blog.csdn.net/jiyueqianxue/article/details/83377181

2.Jackson

依赖包：3个， jackson-core：核心包；jackson-annotations：注解包；jackson-databind：数据绑定包。

• The Jackson ObjectMapper which parses JSON into custom Java objects, or into a Jackson specific tree structure (tree model).
• The Jackson JsonParser which is Jackson‘s JSON pull parser, parsing JSON one token at a time.

参考：

http://tutorials.jenkov.com/java-json/index.html

https://www.cnblogs.com/fanblogs/p/11153010.html