Java getClass returns 不同class

Question

我正在尝试创建其中包含文本字段的对话框。代码如下

private void showBatchDialog() {
    Dialog<Batch> dialog = new Dialog<Batch>();
    dialog.setTitle("Add batch");
    dialog.setHeaderText("adding new batch");

    ButtonType addButtonType = new ButtonType("Add batch",
            ButtonData.OK_DONE);

    Collection<ButtonType> buttons = new ArrayList<ButtonType>();
    buttons.add(addButtonType);
    buttons.add(ButtonType.CANCEL);

    dialog.getDialogPane().getButtonTypes().addAll(buttons);

    GridPane grid = new GridPane();
    grid.setHgap(10);
    grid.setVgap(10);
    grid.setPadding(new Insets(20, 150, 10, 10));

    TextField code = new TextField();
    code.setPromptText("code");
    TextField name = new TextField();
    name.setPromptText("name");
    grid.add(new Label("code"), 0, 0);
    grid.add(code, 1, 0);
    grid.add(new Label("name"), 0, 1);
    grid.add(name, 1, 1);

    dialog.getDialogPane().setContent(grid);
    dialog.setResultConverter(value -> {
        if (value == addButtonType) {
            return new Batch() {
                {
                    setCode(code.getText());
                    setName(name.getText());
                }
            };
        } else {
            return null;
        }
    });

    Optional<Batch> result = dialog.showAndWait();


    result.ifPresent(consumer -> {
        Batch batch = (Batch) consumer;
        batch.getClass(); // Doesn't returns Batch class
    });
}

因此，当我尝试通过对话框 class 返回时，它不会 returns 批处理。问题是如何获得 Batch class?

Batch class 的正文如下

@Entity
public class Batch {
    @Id
    @GeneratedValue(generator="uuid")
    @GenericGenerator(name="uuid", strategy="uuid2")
    @Column(name="batch_id")
    private String uuid;
    @NotNull(message="Code field could not be an empty")
    @Column(unique=true)
    private String code;
    private String name;

    @OneToMany(mappedBy = "batch", cascade = CascadeType.ALL)
    private Collection<Product> products = new ArrayList<Product>();

    public Collection<Product> getProducts() {
        return products;
    }

    public void setProducts(Collection<Product> products) {
        this.products = products;
    }

    public String getCode() {
        return code;
    }

    public void setCode(String code) {
        this.code = code;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getUuid() {
        return uuid;
    }

    public void setUuid(String uuid) {
        this.uuid = uuid;
    }

}

Answer 1

您创建了扩展 Batch 的匿名 class 实例。替换您的 if 语句

if (value == addButtonType) {
     return new Batch() {
        {
            setCode(code.getText());
            setName(name.getText());
        }
     };
}

使用以下代码：

    if (value == addButtonType) {
        Batch b = new Batch();
        b.setCode(code.getText());
        b.setName(name.getText());
        return b;
    }

Answer 2

在 java 中，对象的 getClass() 方法 returns Class<? extends Object>，因此您不会期望得到 Batch 作为结果此代码 - 相反，您应该期望 Class.

的实例

Java getClass returns 不同class

Java getClass returns different class

java

javafx

javafx-8