我目前通過一個構造函數傳遞我的數據，該構造函數填充從我的抽象類和擴展類（即擴展的 MusicItem Abstract 和 CD 和 Vinyl 類）請求的數據我試圖從我的控制器使用 JavaFX 將它們打印到表視圖中，但即使放置了 system.out 行也沒有顯示任何內容。我已經嘗試將它們放入可觀察列表以及普通數組列表中，我已經三次檢查數據字段以查看它們是否與表格匹配并且我嘗試在輸入時查看對象但是當我這樣做時，該對象的十六進制代碼出現。它正確連接到數據庫但不顯示任何內容abstract class MusicItem {    @Id    private int songID;    private String name;    private String artist;    private String genre;    private String releaseDate;    private double price;public MusicItem(int songID, String name, String artist, String genre, String releaseDate, double price) {    this.songID = songID;    this.name = name;    this.artist = artist;    this.genre = genre;    this.releaseDate = releaseDate;    this.price = price;    }}@Entityclass Vinyl extends MusicItem{private double speed;private double diameter;Vinyl(int songID, String name, String artist, String genre, String releaseDate, double price, double speed, double diameter) {    super(songID, name, artist, genre, releaseDate, price);    this.speed = speed;    this.diameter = diameter;    }}@Entityclass CD extends MusicItem{private double duration;CD(int songID, String name, String artist, String genre, String releaseDate, double price, double duration) {    super(songID, name, artist, genre, releaseDate, price);    this.duration = duration;   }}