Java?json轉換實體類(JavaBean)及實體類(JavaBean)轉換json代碼示例

更新時間：2024年12月30日 09:48:28 作者：深林中的書海

這篇文章主要介紹了兩種常見的JSON與Java實體類相互轉換的方法,分別是使用庫Jackson、Gson、Fastjson和在線工具,無論是將JSON轉換為Java實體類還是將Java實體類轉換為JSON,這些方法都能顯著簡化開發(fā)過程,需要的朋友可以參考下

JSON轉換實體類

1. 使用Jackson庫

public class User {
    private String name;
    private int age;
    // getters and setters
}

import com.fasterxml.jackson.databind.ObjectMapper;

public class JsonDemo {
    public static void main(String[] args) {
        String json = "{\"name\":\"John\", \"age\":30}";
        ObjectMapper mapper = new ObjectMapper();
        try {
            User user = mapper.readValue(json, User.class);
            System.out.println(user.getName());
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

2. 使用Gson庫

<dependency>
    <groupId>com.google.code.gson</groupId>
    <artifactId>gson</artifactId>
    <version>2.8.6</version>
</dependency>

public class User {
    private String name;
    private int age;
    // getters and setters
}

import com.google.gson.Gson;

public class JsonDemo {
    public static void main(String[] args) {
        String json = "{\"name\":\"John\", \"age\":30}";
        Gson gson = new Gson();
        User user = gson.fromJson(json, User.class);
        System.out.println(user.getName());
    }
}

3. 使用Fastjson庫

<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>fastjson</artifactId>
    <version>2.0.15</version>
</dependency>

public class User {
    private String name;
    private int age;
    // getters and setters
}

import com.alibaba.fastjson.JSON;

public class JsonDemo {
    public static void main(String[] args) {
        String json = "{\"name\":\"John\", \"age\":30}";
        User user = JSON.parseObject(json, User.class);
        System.out.println(user.getName());
    }
}

4.在線工具

此外，還有一些在線工具可以幫助你將JSON轉換為Java實體類，例如：

JSON中文網的在線JSON轉JavaBean工具：https://www.json.cn/json2java/

這些工具和庫可以幫助開發(fā)者更方便地將JSON數(shù)據(jù)轉換為Java對象，從而簡化數(shù)據(jù)處理過程。

實體類轉換JSON

1. 使用Jackson庫

<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-databind</artifactId>
    <version>2.13.0</version>
</dependency>

public class User {
    private String name;
    private int age;
    // getters and setters
}

import com.fasterxml.jackson.databind.ObjectMapper;

public class JsonDemo {
    public static void main(String[] args) {
        User user = new User();
        user.setName("John");
        user.setAge(30);
        ObjectMapper mapper = new ObjectMapper();
        try {
            String json = mapper.writeValueAsString(user);
            System.out.println(json);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

2. 使用Gson庫

<dependency>
    <groupId>com.google.code.gson</groupId>
    <artifactId>gson</artifactId>
    <version>2.8.6</version>
</dependency>

public class User {
    private String name;
    private int age;
    // getters and setters
}

import com.google.gson.Gson;

public class JsonDemo {
    public static void main(String[] args) {
        User user = new User();
        user.setName("John");
        user.setAge(30);
        Gson gson = new Gson();
        String json = gson.toJson(user);
        System.out.println(json);
    }
}

3. 使用Fastjson庫

<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>fastjson</artifactId>
    <version>2.0.15</version>
</dependency>

public class User {
    private String name;
    private int age;
    // getters and setters
}

import com.alibaba.fastjson.JSON;

public class JsonDemo {
    public static void main(String[] args) {
        User user = new User();
        user.setName("John");
        user.setAge(30);
        String json = JSON.toJSONString(user);
        System.out.println(json);
    }
}