英文:
Quarkus Kotlin init block called multiple times
问题
我正在尝试在Quarkus框架中使用Kotlin。我需要在应用程序启动时初始化一些值，所以我使用了Kotlin的init和Quarkus的@Startup。我按照以下方式操作：
@Startup
@ApplicationScoped
class Initializer() {
init {
println("初始化变量")
}
}
我期望字符串"初始化变量"只会被打印一次，但它被打印了两次。似乎Quarkus多次初始化了带有@ApplicationScoped注解的相同类。
我需要初始化只执行一次，否则在代码中尝试使用初始化变量时会出现引用问题。这是正确的方式吗？还有其他方法吗？
英文:
I am trying to use Kotlin with the Quarkus framework. I need to initialize some values at application startup so I have used init from Kotlin and @Startup from Quarkus.
I do as following:
@Startup
@ApplicationScoped
class Initializer() {
init {
println("Init Variables")
}
}
I expected that the string Init Variables would be printed only once time, but it was printed two times. It seems that Querkus initialize the same classes annotated with @ApplicationScoped multiple times.
I need that the initialization is executed only once otherwise I have reference trouble when I am trying to use initialized variables in the code. Is it the correct way?There is another way do that?
答案1
得分: 1
以下是翻译好的部分：
有两种方法的混合。在 Kotlin 中，init 将在类初始化后被调用，可以将其视为默认构造函数（如果有其他构造函数，它们将调用此默认构造函数）。
一种选择是使用 @Observes startupEvent: StartupEvent，例如：
import io.quarkus.runtime.StartupEvent
import jakarta.enterprise.context.ApplicationScoped
import jakarta.enterprise.event.Observes
@ApplicationScoped
class Initializer() {
fun myInit(@Observes startupEvent: StartupEvent) {
println("Init Variables")
}
}
如果真的想要，仍然可以拥有 init 方法，因为这个 @Observes 将强制初始化 bean，并触发 init 方法。
英文:
There's a mix up of two approaches. In Kotlin, init will be called once the class is initialized, think about it as a default constructor(and if there're other constructors, they'll call this default constructor).
One option is to use @Observes startupEvent: StartupEvent, e.g:
import io.quarkus.runtime.StartupEvent
import jakarta.enterprise.context.ApplicationScoped
import jakarta.enterprise.event.Observes
@ApplicationScoped
class Initializer() {
fun myInit(@Observes startupEvent: StartupEvent) {
println("Init Variables")
}
}
You can still have init method if you really want, since this @Observes will force-init the bean and this will trigger the init method.
通过集体智慧和协作来改善编程学习和解决问题的方式。致力于成为全球开发者共同参与的知识库，让每个人都能够通过互相帮助和分享经验来进步。
评论