CDI 构造函数注入不适用于瞬态不可序列化依赖项
我非常喜欢 CDI 的构造函数注入，但现在我发现了一个用例，其中构造函数注入显然无法按预期工作。
在我的示例中，我有两个课程。类“BeanA”没有定义明确的范围，并且不实现 Serialized。类“BeanB”用@SessionScoped注释并且实现了Serialized。
public class BeanA{
}
@SessionScoped
public class BeanB implements Serializable{
@Inject
private BeanA beanA;
}
当我尝试将 BeanA 的实例注入到 BeanB 中时，我从 Weld 收到 UnserializedDependencyException，因为 BeanA 不可序列化。这是预期的行为。
当我用“transient”标记字段“beanA”时，注入工作没有问题：
@Inject
private transient BeanA beanA;
现在 Weld 不会抛出任何异常。
这对我来说非常好，但是当我想通过构造函数注入来实现这一点时，我的理解问题就出现了。当我执行以下操作时，它不再起作用：
@SessionScoped
public class BeanB implements Serializable{
private transient BeanA beanA;
@Inject
public BeanB(BeanA beanA){
this.beanA = beanA;
}
public BeanB(){}
}
使用此代码，我再次收到 UnserializedDependencyException。我认为构造函数注入和字段注入或多或少是等效的，但显然它们不是。我的错误是什么？
I like the constructor injection of CDI a lot but now I found a usecase where constructor injection apparently doesn't work as expected.
In my example I have two classes. Class "BeanA" has no explicit scope defined and does not implement Serializable. Class "BeanB" is annotated with @SessionScoped and does implement Serializable.
public class BeanA{
}
@SessionScoped
public class BeanB implements Serializable{
@Inject
private BeanA beanA;
}
When I try to inject an instance of BeanA into BeanB of cource I get an UnserializableDependencyException from Weld because BeanA isn't serializable. This is the expected behaviour.
When I mark the field "beanA" with "transient" the injection works without problems:
@Inject
private transient BeanA beanA;
Now Weld doesn't throw any exceptions.
This is perfectly fine for me but my understanding problem comes when I like to get this working with constructor injection. When I do the following it doesn't work anymore:
@SessionScoped
public class BeanB implements Serializable{
private transient BeanA beanA;
@Inject
public BeanB(BeanA beanA){
this.beanA = beanA;
}
public BeanB(){}
}
With this code I get the UnserializableDependencyException again. I thought that constructor injection and field injection are more or less equivalent but obviously they aren't. What is my mistake?
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这似乎是一个错误。如果使 BeanA 可序列化，一切都会正常吗？另外您使用的是哪个版本的 Weld？
That seems like a bug. Does everything work well if you make BeanA serializable? Also which version of Weld are you using?