Question

我正在使用聊天应用程序，我想存储消息的时间戳。我的消息数据类是：

import com.google.firebase.firestore.ServerTimestamp;
import java.util.Date;

public class messgaesDataClass {
    private String messageText;
    private int messageStatus;
    private String messagefrom;
    private @ServerTimestamp Date timestamp;

    public messgaesDataClass(String messageText, int messageStatus, String messagefrom, Date time) {
        this.messageText = messageText;
        this.messageStatus = messageStatus;
        this.messagefrom = messagefrom;
        this.time = time;
    }

    public messgaesDataClass() {
    }

    public String getMessageText() {
        return messageText;
    }

    public void setMessageText(String messageText) {
        this.messageText = messageText;
    }

    public int getMessageStatus() {
        return messageStatus;
    }

    public void setMessageStatus(int messageStatus) {
        this.messageStatus = messageStatus;
    }

    public String getMessagefrom() {
        return messagefrom;
    }

    public void setMessagefrom(String messagefrom) {
        this.messagefrom = messagefrom;
    }

    public Date getTime() {
        return time;
    }

    public void setTime(Date time) {
        this.time = time;
    }
}

我不明白如何制作此类的对象。我可以在此类的构造函数中传递什么以初始化timestamp属性？

Answer 1

要解决此问题，应删除Date time作为构造函数的参数。您的构造函数应如下所示：

public messgaesDataClass(String messageText, int messageStatus, String messagefrom) {
    this.messageText = messageText;
    this.messageStatus = messageStatus;
    this.messagefrom = messagefrom;
}

您无需在构造函数中初始化time对象。 Firebase服务器将读取您的time字段，因为它是一个ServerTimestamp（由于有注释），并将相应地使用服务器时间戳填充该字段。

如何在Firestore中保存时间戳？

1 个答案: