如何在 SQLite Room 数据库中自动生成时间戳？

Question

我在 Android Studio 中为 RoomDatabase 创建实体 class 以定义 Table。我不知道如何在实体中自动生成时间戳。是否有任何注释可用，如@PrimaryKey(autogenerate=true)?

@Entity(tableName = "userTable")
public class DataEntity {
    @PrimaryKey(autoGenerate = true)
    private int id;
    @NonNull
    @ColumnInfo(name = "requirement")
    private String requirement;

    @NonNull
    @ColumnInfo(name = "timestamp")
    private String timestamp;

}

Answer 1

希望对您有所帮助

@Entity(tableName = "userTable")
public class DataEntity {
    @PrimaryKey(autoGenerate = true)
    private int id;
    @NonNull
    @ColumnInfo(name = "requirement")
    private String requirement;

    @NonNull
    @ColumnInfo(name = "timestamp")
    private String timestamp = String.valueOf(TimeUnit.MILLISECONDS.toSeconds(System.currentTimeMillis()));

}