json格式

{userId:'1',message:'2',create_time:'2020-03-28 20:58:11',create_date:'2020-03-28'}


JAVA对象

ChatDTO.java

public class ChatDTO {
    private String userId;
    private String message;
    private String createDate;
    private String createTime;
}

......
get set 方法

JSONObject object = JSONObject.fromObject(json); //先转成json对象
ChatDTO chatDTO = (ChatDTO) JSONObject.toBean(object, ChatDTO.class);