渴望ApplicationScoped托管bean构建多次

问题描述

我有一堆渴望 ApplicationScoped 托管bean。其中一些是通过 ManagedProperty 注释注入其他注释，形成依赖树。每个依赖bean在构造之后操纵它的父级。

I have a bunch of eager ApplicationScoped managed beans. Some of them are injected into others by the ManagedProperty annotation, forming a tree of dependencies. Each depending bean manipulates its parent after construction.

然而，似乎为每次注入创建了一个新实例，从而使之前的操作被撤消。据我了解，只应创建一次 ApplicationScoped bean。我误解了或者为什么会这样？是因为他们渴望？

However, it seems like a new instance is created for each injection, thus making previous manipulations undone. To my understanding, an ApplicationScoped bean should only be created once. Have I misunderstood or why is this happening? Is it because they are eager?

这是一个例子：

package example;

import javax.annotation.PostConstruct;
import javax.faces.bean.ApplicationScoped;
import javax.faces.bean.ManagedBean;

@ManagedBean(eager = true)
@ApplicationScoped
public class ParentBean
{
    static int initCount = 0;

    // ...

    @PostConstruct
    public void init()
    {
        ++initCount; // Will end up being between 1 and 3. Expected always 1.

        // ...
    }
}

Child1Bean.java

Child1Bean.java

package example;

import javax.annotation.PostConstruct;
import javax.faces.bean.ApplicationScoped;
import javax.faces.bean.ManagedBean;
import javax.faces.bean.ManagedProperty;

@ManagedBean(eager = true)
@ApplicationScoped
public class Child1Bean
{
    @ManagedProperty("#{parentBean}") ParentBean parentBean;

    public ParentBean getParentBean()
    {
        return parentBean;
    }

    public void setParentBean(ParentBean parentBean)
    {
        this.parentBean = parentBean;
    }

    @PostConstruct
    public void init()
    {
        // manipulate parentBean
    }
}

Child2Bean.java

Child2Bean.java

package example;

import javax.annotation.PostConstruct;
import javax.faces.bean.ApplicationScoped;
import javax.faces.bean.ManagedBean;
import javax.faces.bean.ManagedProperty;

@ManagedBean(eager = true)
@ApplicationScoped
public class Child2Bean
{
    @ManagedProperty("#{parentBean}") ParentBean parentBean;

    public ParentBean getParentBean()
    {
        return parentBean;
    }

    public void setParentBean(ParentBean parentBean)
    {
        this.parentBean = parentBean;
    }

    @PostConstruct
    public void init()
    {
        // manipulate parentBean
    }
}

推荐答案

我希望在Tomcat 8 + Mojarra 2.2.0上解决这个问题。
在我的情况下，我刚从web.xml中删除了监听器声明

I have hopefully resolved this problem on Tomcat 8 + Mojarra 2.2.0.In my case I just removed listener declaration from web.xml

<listener>
    <listener-class>com.sun.faces.config.ConfigureListener</listener-class>
</listener>

之后似乎会调用构造函数。

Constructor seems to be called once afterwards.

关于听众的录入，有一部分BalusC回答了问题。

About listener entry, there is a part of BalusC answer of this question.

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