实体类对象和map集合相互转化的常用方法

准备数据

@Data
@Builder
@NoArgsConstructor
@AllArgsConstructor
public class User {
    private String    account;
    private String    name;
    private String    password;
    private String    mobile;
}

第一种：使用Hutool工具

public class testClass {
    public static void main(String[] args) {
        
        User user = User.builder()
                .account("001")
                .name("张三")
                .password("123456")
                .mobile("12345678912")
                .build();
        System.out.println(user);//输出：User(account=001, name=张三, password=123456, mobile=12345678912)
        
        //将对象转换为 Map
        Map<String, Object> map = BeanUtil.beanToMap(user);
        System.out.println(map);//输出：{account=001, name=张三, password=123456, mobile=12345678912}
        //将map转换为 对象
        User user1 = BeanUtil.toBean(map, User.class);
        System.out.println(user1.getName());//输出：张三
        // 使用CopyOptions自定义转换规则(name字段不进行转换)
        CopyOptions options = CopyOptions.create();
        options.setIgnoreProperties("name");
        User user2 = BeanUtil.toBean(map, User.class, options);
        System.out.println(user2);//输出：User(account=001, name=null, password=123456, mobile=12345678912)
        
    }
}

第二种：使用 FastJosn 

  2.1 fastJson的TypeReference

FastJsonhttps://so.csdn.net/so/search?q=FastJson&spm=1001.2101.3001.7020

public class testClass {
    public static void main(String[] args) {
       
        User user = User.builder()
                .account("001")
                .name("张三")
                .password("123456")
                .mobile("12345678912")
                .build();
        System.out.println(user);//输出：User(account=001, name=张三, password=123456, mobile=12345678912)

        //将对象user转化为map集合
        userMap = JSON.parseObject(JSON.toJSONString(user), new TypeReference<>(){});
        System.out.println(userMap.get("mobile"));//输出：12345678912
        
        //将map集合转化为对象user1
        User user1 = JSON.parseObject(JSON.toJSONString(userMap), new TypeReference<>(){});
        System.out.println(user1.getName()); //输出：张三 
        
    }
}

   2.2 通过Java对象和JSON之间的转换。

public class testClass {
    public static void main(String[] args) {
        
        User user = User.builder()
                .account("001")
                .name("张三")
                .password("123456")
                .mobile("12345678912")
                .build();
        System.out.println(user);//输出：User(account=001, name=张三, password=123456, mobile=12345678912)
        
//将对象user转化为map集合(var是JDK10新特性)
        var map = JSON.parseObject(JSON.toJSONString(user), Map.class);
        System.out.println(map);//输出：{password=123456, mobile=12345678912, name=张三, account=001}

        //将map集合转化为对象user1
        User user1 = JSON.parseObject(JSON.toJSONString(map), User.class);
        System.out.println(user1);//输出：User(account=001, name=张三, password=123456, mobile=12345678912)
        
    }
}