Question

我在json文件中收集了推文。我想对它们进行操作，例如根据每个数据条目的时间和坐标对推文进行分组。目前对于对象坐标我在List数据类型中有它们。与时间和日期相似。所以我已经成功地解析了它们，但是我很难对它们进行操作，尤其是数据时间和坐标。

最终目标是让我可以更轻松地对它们进行操作。

如何将List数据类型转换为双重存储？
我不确定我应该将什么数据类型用于时间和日期

这是json元素的一个例子

{"text": "Flood/Storm/Tree Down. Northern Beaches (King Rd, Ingleside, NSW 2101) at 6 Mar 2017 21:38, 
"user": {"id": "4721717942", "name": "NSW Fire Updates"}, "lang": "en", 
"coordinates": { "coordinates": [151.264811, -33.6848] , "type":"Point"}, "created_at": "Mon Mar 06 10:44:31 +0000 2017"}

这是我制作的坐标类

public class Coordinates {
    private String type;
    private List<String> coordinates;
    public String getType (){
        return type;
    }
    public void setType (String type){
        this.type = type;
    }
    public List<String> getCoordinates(){
        return coordinates;
    }
    public void setCoordinates (List<String> coordinates){
        this.coordinates = coordinates;
    }


 @Override
    public String toString(){
        return "[type = "+type+", coordinates = "+coordinates+"]";
     }
}

这是包含时间和日期的课程

@JsonIgnoreProperties(ignoreUnknown = true)
public class Tweet {
    private String text;
    private String created_at;
    private User user;
    private Coordinates coordinates;

    public Tweet(){
    }

    public String getText()
    {
        return text;
    }
    public void setText(String text)
    {
        this.text = text;
    }
    public String getCreated_at()
    {
        return created_at;
    }
    public void setCreated_at(String created_at)
    {
        this.created_at = created_at;
    }
    public User getUser()
    {
        return user;
    }
    public void setUser(User user)
    {
        this.user = user;
    }
    public Coordinates getCoordinates()
    {
        return coordinates;
    }
    public void setCoordinates(Coordinates coordinates)
    {
        this.coordinates = coordinates;
    }

    @Override
    public String toString()
    {
        return "[text = "+text+", created_at = "+created_at+", user = "+user+", coordinates = "+coordinates+"]";
    }
}

Answer 1

尝试了解java 8流图和过滤操作，您可以在一行代码中完成您的工作。 https://docs.oracle.com/javase/8/docs/api/java/util/stream/package-summary.html或者如果您不能使用java 8，请从此帖子中尝试此示例Sorting Java objects using multiple keys

协调Jackson中的操作数据类型

1 个答案: