如何在运行时获得DiscriminatorValue [英] How to get the DiscriminatorValue at run time

问题描述

We have the following classes

@Entity
@Inheritance(strategy = InheritanceType.SINGLE_TABLE) // optional annotation as this is default
@DiscriminatorColumn(name = "apType", discriminatorType = DiscriminatorType.STRING, length = 255)
@DiscriminatorValue("AP")
public class ApplicationProcess {
}

而且

And this

@Entity
@DiscriminatorValue("APS")
public class ApplicationProcessScheme extends ApplicationProcess {
}

现在我需要在运行时知道 ApplicationProcess 是否为 DiscriminatorValue AP或APS 。
因为这是由jpa自动处理的，所以我无法得到这个值。

Now I need to know at runtime if the ApplicationProcess is of DiscriminatorValue AP or APS. Since this is automatically handled by jpa, I have no way of getting this value.

我们调用一个方法，它需要一个 ApplicationProcess 作为参数，我想避免使用 instanceof 来检查它是什么类型。如果我可以做一些类似的事情，会更酷。

We are calling a method that takes an ApplicationProcess as parameter, and I want to avoid using instanceof to check what type it is. Would be cooler if I could do something like

applicationProcess.getApType().equals("AP");

推荐答案

您可以将您的鉴别器映射为只读属性：

You can map your discriminator as a read-only property:

public class ApplicationProcess { 

    ...

    @Column(name = "apType", insertable = false, updatable = false)
    private String apType;

}

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