Guide to use the JSON conversion framework in the Java class library

Guide to use the JSON conversion framework in the Java class library introduction: JSON (JavaScript Object Notation) is a lightweight data exchange format that is widely used in Web development and data transmission.In Java development, there are many excellent JSON conversion frameworks to choose from, such as GSON, Jackson, Fastjson, etc.This article will introduce how to use these frameworks to realize the mutual conversion between JSON objects and Java objects in the Java program. 1. The use of GSON: 1. Add dependencies: In the Maven project, you need to add the following dependencies to the POM.XML file: <dependency> <groupId>com.google.code.gson</groupId> <artifactId>gson</artifactId> <version>2.8.7</version> </dependency> 2. Convert java objects to JSON string: import com.google.gson.Gson; Gson gson = new Gson(); String json = gson.toJson(obj); `Obj` is the Java object to be converted,` json` is the conversion JSON string. 3. Convert JSON string to Java object: import com.google.gson.Gson; Gson gson = new Gson(); MyClass obj = gson.fromJson(json, MyClass.class); `JSON` to the JSON string to be converted,` myclass` is a class of Java objects. 2. Jackson's use: 1. Add dependencies: In the Maven project, you need to add the following dependencies to the POM.XML file: <dependency> <groupId>com.fasterxml.jackson.core</groupId> <artifactId>jackson-databind</artifactId> <version>2.12.1</version> </dependency> 2. Convert java objects to JSON string: import com.fasterxml.jackson.databind.ObjectMapper; ObjectMapper objectMapper = new ObjectMapper(); String json = objectMapper.writeValueAsString(obj); `Obj` is the Java object to be converted,` json` is the conversion JSON string. 3. Convert JSON string to Java object: import com.fasterxml.jackson.databind.ObjectMapper; ObjectMapper objectMapper = new ObjectMapper(); MyClass obj = objectMapper.readValue(json, MyClass.class); `JSON` to the JSON string to be converted,` myclass` is a class of Java objects. 3. Fastjson use: 1. Add dependencies: In the Maven project, you need to add the following dependencies to the POM.XML file: <dependency> <groupId>com.alibaba</groupId> <artifactId>fastjson</artifactId> <version>1.2.78</version> </dependency> 2. Convert java objects to JSON string: import com.alibaba.fastjson.JSON; String json = JSON.toJSONString(obj); `Obj` is the Java object to be converted,` json` is the conversion JSON string. 3. Convert JSON string to Java object: import com.alibaba.fastjson.JSON; MyClass obj = JSON.parseObject(json, MyClass.class); `JSON` to the JSON string to be converted,` myclass` is a class of Java objects. in conclusion: This article introduces three commonly used JSON conversion frameworks: GSON, Jackson, and Fastjson, and their usage in Java.Through these frameworks, we can easily realize the mutual conversion between JSON objects and Java objects.When choosing to use the framework, you can choose according to the actual project needs and personal preferences. The above is the guideline of the JSON conversion framework in the Java library. I hope this article will help you!