blocks|key|1277572|text|你有没有在这个链接上尝试过类似的方法？我不确定createValueBinding()是否仍然可用，但是像这样的代码应该可以从普通的旧Servlet访问。这确实要求bean已经存在。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1277573|http://www.coderanch.com/t/211706/JSF/java/access-managed-bean-JSF-from|1277574|+FacesContext+context+=+FacesContext.getCurrentInstance();++
+Application+app+=+context.getApplication();
+//+May+be+deprecated
+ValueBinding+binding+=+app.createValueBinding("#{"+%2B+expr+%2B+"}");+
+Object+value+=+binding.getValue(context);|code-block|syntax|javascript|1277575|entityMap|0|LINK|mutability|MUTABLE|url^0|N|K|0|0|1Z|0|0|0^^$0|@$1|2|3|4|5|6|7|T|8|@$9|U|A|V|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|W|8|@]|D|@$9|X|A|Y|1|Z]]|E|$]]|$1|H|3|I|5|J|7|10|8|@]|D|@]|E|$K|L]]|$1|M|3|-4|5|6|7|11|8|@]|D|@]|E|$]]]|N|$O|$5|P|Q|R|E|$S|G]]]]

Have you tried an approach like on this link? I'm not sure if <code>createValueBinding()</code> is still available but code like this should be accessible from a plain old Servlet. This does require to bean to already exist.

<a href="http://www.coderanch.com/t/211706/JSF/java/access-managed-bean-JSF-from" rel="nofollow noreferrer">http://www.coderanch.com/t/211706/JSF/java/access-managed-bean-JSF-from</a>

<pre><code> FacesContext context = FacesContext.getCurrentInstance(); 
 Application app = context.getApplication();
 // May be deprecated
 ValueBinding binding = app.createValueBinding("#{" + expr + "}"); 
 Object value = binding.getValue(context);
</code></pre>

blocks|key|1277595|text|我使用以下方法：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1277596|public+static+<T>+T+getBean(final+String+beanName,+final+Class<T>+clazz)+{
++++ELContext+elContext+=+FacesContext.getCurrentInstance().getELContext();
++++return+(T)+FacesContext.getCurrentInstance().getApplication().getELResolver().getValue(elContext,+null,+beanName);
}|code-block|syntax|javascript|1277597|这允许我以类型化的方式获取返回的对象。|1277598|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

I use the following method:

<pre><code>public static &lt;T&gt; T getBean(final String beanName, final Class&lt;T&gt; clazz) {
 ELContext elContext = FacesContext.getCurrentInstance().getELContext();
 return (T) FacesContext.getCurrentInstance().getApplication().getELResolver().getValue(elContext, null, beanName);
}
</code></pre>

This allows me to get the returned object in a typed manner.

blocks|key|1062925|text|您可以通过传递以下名称来获取托管bean：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1062926|public+static+Object+getBean(String+beanName){
++++Object+bean+=+null;
++++FacesContext+fc+=+FacesContext.getCurrentInstance();
++++if(fc!=null){
+++++++++ELContext+elContext+=+fc.getELContext();
+++++++++bean+=+elContext.getELResolver().getValue(elContext,+null,+beanName);
++++}

++++return+bean;
}|code-block|syntax|javascript|1062927|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

You can get the managed bean by passing the name:

<pre><code>public static Object getBean(String beanName){
 Object bean = null;
 FacesContext fc = FacesContext.getCurrentInstance();
 if(fc!=null){
 ELContext elContext = fc.getELContext();
 bean = elContext.getELResolver().getValue(elContext, null, beanName);
 }

 return bean;
}
</code></pre>

blocks|key|1063016|text|我使用的是：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1063017|public+static+<T>+T+getBean(Class<T>+clazz)+{
++++try+{
++++++++String+beanName+=+getBeanName(clazz);
++++++++FacesContext+facesContext+=+FacesContext.getCurrentInstance();
++++++++return+facesContext.getApplication().evaluateExpressionGet(facesContext,+"#{"+%2B+beanName+%2B+"}",+clazz);
++++//return+facesContext.getApplication().getELResolver().getValue(facesContext.getELContext(),+null,+nomeBean);
++++}+catch+(Exception+ex)+{
++++++++return+null;
++++}
}

public+static+<T>+String+getBeanName(Class<T>+clazz)+{
++++ManagedBean+managedBean+=+clazz.getAnnotation(ManagedBean.class);
++++String+beanName+=+managedBean.name();

++++if+(StringHelper.isNullOrEmpty(beanName))+{
++++++++beanName+=+clazz.getSimpleName();
++++++++beanName+=+Character.toLowerCase(beanName.charAt(0))+%2B+beanName.substring(1);
++++}

++++return+beanName;
}|code-block|syntax|javascript|1063018|然后打电话给：|1063019|MyManageBean+bean+=+getBean(MyManageBean.class);|1063020|通过这种方式，您可以重构代码并跟踪使用情况，而不会出现任何问题。|1063021|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Q|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|S|8|@]|9|@]|A|$]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

I use this:

<pre><code>public static &lt;T&gt; T getBean(Class&lt;T&gt; clazz) {
 try {
 String beanName = getBeanName(clazz);
 FacesContext facesContext = FacesContext.getCurrentInstance();
 return facesContext.getApplication().evaluateExpressionGet(facesContext, "#{" + beanName + "}", clazz);
 //return facesContext.getApplication().getELResolver().getValue(facesContext.getELContext(), null, nomeBean);
 } catch (Exception ex) {
 return null;
 }
}

public static &lt;T&gt; String getBeanName(Class&lt;T&gt; clazz) {
 ManagedBean managedBean = clazz.getAnnotation(ManagedBean.class);
 String beanName = managedBean.name();

 if (StringHelper.isNullOrEmpty(beanName)) {
 beanName = clazz.getSimpleName();
 beanName = Character.toLowerCase(beanName.charAt(0)) + beanName.substring(1);
 }

 return beanName;
}
</code></pre>

And then call:

<pre><code>MyManageBean bean = getBean(MyManageBean.class);
</code></pre>

This way you can refactor your code and track usages without problems.

blocks|key|1063108|text|我也有同样的要求。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1063109|我已经使用了下面的方法来获得它。|1063110|我有会话作用域的bean。|1063111|@ManagedBean(name="mb")
@SessionScopedpublic+
class+ManagedBean+{
+++++--------
}|code-block|syntax|javascript|1063112|我在我的servlet+doPost()方法中使用了以下代码。|1063113|ManagedBean+mb+=+(ManagedBean)+request.getSession().getAttribute("mb");|1063114|它解决了我的问题。|1063115|entityMap^0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|T|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|U|8|@]|9|@]|A|$]]|$1|F|3|G|5|H|7|V|8|@]|9|@]|A|$I|J]]|$1|K|3|L|5|6|7|W|8|@]|9|@]|A|$]]|$1|M|3|N|5|H|7|X|8|@]|9|@]|A|$I|J]]|$1|O|3|P|5|6|7|Y|8|@]|9|@]|A|$]]|$1|Q|3|-4|5|6|7|Z|8|@]|9|@]|A|$]]]|R|$]]

I had same requirement. 

I have used the below way to get it. 

I had session scoped bean. 

<pre><code>@ManagedBean(name="mb")
@SessionScopedpublic 
class ManagedBean {
 --------
}
</code></pre>

I have used the below code in my servlet doPost() method. 

<pre><code>ManagedBean mb = (ManagedBean) request.getSession().getAttribute("mb");
</code></pre>

it solved my problem.

I'm trying to write a custom servlet (for AJAX/JSON) in which I would like to reference my <code>@ManagedBeans</code> by name. I'm hoping to map:

<code>http://host/app/myBean/myProperty</code>

to: 

<pre><code>@ManagedBean(name="myBean")
public class MyBean {
 public String getMyProperty();
}
</code></pre>

Is it possible to load a bean by name from a regular servlet? Is there a JSF servlet or helper I could use for it?

I seem to be spoilt by Spring in which all this is too obvious.

Get JSF managed bean by name in any Servlet related class

JSON

我正在尝试编写一个自定义servlet (用于AJAX/JSON)，在其中我希望通过名称引用我的@ManagedBeans。我希望映射到：http://host/app/myBean/myProperty至：@ManagedBean(name="myBean")public class MyBean {    publ...

问在任何与Servlet相关的类中按名称获取JSF托管bean
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