@Scope("request")无效 [英] @Scope("request") not working

问题描述

我正在尝试JSF和Primefaces(JSF 2.0.2，PrimeFaces 3.0.5，Spring 3.0.0).看来我无法从

之类的xhtml页面访问托管bean.

<h:inputText  id="lastName" value="#{personalBean.personal_Basic.firstName}"  label="Last Name"  required="true" />

请求从命令链接对bean方法，服务的调用开始，并返回页面.我可以在服务器控制台Bean中看到服务方法已执行.当我尝试使用上述bean属性时，我什么也没看到.但是，我能够访问用于用户会话管理的会话作用域bean.

很抱歉，这个问题太天真了.任何解决问题的建议都将受到赞赏.

下面是我的代码片段.这就是我所说的bean:

<h:form>
    <p:commandLink id="ajax" actionListener="#{personalBean.getPersonalInfo}" style="margin-left:5px;">  
        <h:outputText value="Personal Info" />  <br/>
    </p:commandLink>  
</h:form>

下面是请求范围内的托管Bean.

package com.test.model;
@ManagedBean
@Scope("request")
public class PersonalBean  implements Serializable {

private static final long serialVersionUID = 199L;
private Personal_Basic personal_Basic;
private IPersonalService personalService;

@Inject
public PersonalBean(final IPersonalService personalService) {
    this.personalService = personalService;
}
public String getPersonalInfo() {
    System.out.println("\n\nPersonalBean#getPersonalInfo called...**");
    User user = null;
    Personal_Basic personal_Basic = personalService.getPersonalBasic();
    this.setPersonal_Basic(personal_Basic);
    System.out.println("personal_Basic data:"+personal_Basic);
    System.out.println("PersonalBean#getPersonalInfo ended...");
    return "/page/personal.html";
}
// Getters/setters for class members followed
}

PersonalService的实现使用@Service进行注释.

以下是spring配置xml的摘录.

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:p="http://www.springframework.org/schema/p"
    xmlns:aop="http://www.springframework.org/schema/aop"
    xmlns:tx="http://www.springframework.org/schema/tx"
    xmlns:context="http://www.springframework.org/schema/context"
    xsi:schemaLocation="
       http://www.springframework.org/schema/beans
       http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
       http://www.springframework.org/schema/tx
       http://www.springframework.org/schema/tx/spring-tx-3.0.xsd
       http://www.springframework.org/schema/aop
       http://www.springframework.org/schema/aop/spring-aop-3.0.xsd
       http://www.springframework.org/schema/context
       http://www.springframework.org/schema/context/spring-context-3.0.xsd">
    <context:annotation-config/> 
    <context:component-scan base-package="com.test"/>
...................
...................
</beans>

下面是来自faces-config.xml的摘录

<?xml version="1.0"?>
<faces-config xmlns="http://java.sun.com/xml/ns/javaee"
              xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
              xsi:schemaLocation="http://java.sun.com/xml/ns/javaee     http://java.sun.com/xml/ns/javaee/web-facesconfig_2_0.xsd"
              version="2.0">
  <application>
    <el-resolver>org.springframework.web.jsf.el.SpringBeanFacesELResolver</el-resolver>
        <resource-bundle>
            <base-name>Messages</base-name>
            <var>msg</var>
        </resource-bundle>
        <locale-config>
            <default-locale>en</default-locale>
        </locale-config>
  </application>
...........................
</faces-config>

解决方案

默认情况下，<context:component-scan base-package="com.test"/>元素扫描并注册所有带有@ Component，@ Repository，@ Service或@Controller注释的bean.

Spring还提供了对javax.annotation.ManagedBean(不是javax.faces.bean.ManagedBean)和JSR-330标准注释的支持，Spring也对其进行了扫描，但是您需要在项目中添加以下依赖项.

<dependency>
    <groupId>javax.inject</groupId>
    <artifactId>javax.inject</artifactId>
    <version>1</version>
</dependency>

您可以看到所有与Spring注释等效的注释

或者您也可以使用

手动获取Spring bean

org.springframework.web.context.support.WebApplicationContextUtils像这样:

private Object getSpringBean(String name){
        WebApplicationContext ctx = WebApplicationContextUtils.getRequiredWebApplicationContext(
                (ServletContext) FacesContext.getCurrentInstance().getExternalContext().getContext());
        return ctx.getBean(name);
}

并像这样使用它:

Personal_Basic personal_Basic = ((IPersonalService) getSpringBean("personalService")).getPersonalBasic();

但是，除了在您的应用程序中使用两个容器之外，您还可以使用Spring容器通过使用@Component注释JSF Bean来管理所有Bean，并且我没有意识到任何暗示，并且应该完全可以使用春天注释.

另请参阅:

• < context:annotation-config>之间的区别vs< context:component-scan>
• 组件检测的JSR-330支持不一致
• Spring文档- JSF集成
• 使用Spring管理JSF Bean

I am experimenting with JSF and Primefaces ( JSF 2.0.2 ,PrimeFaces 3.0.5, Spring 3.0.0). It seems I am unable to access managed bean from a xhtml page such as

<h:inputText  id="lastName" value="#{personalBean.personal_Basic.firstName}"  label="Last Name"  required="true" />

The request starts from a command link's invocation to bean method, service and returns the page. I could see in servers console Bean, service methods are executed. I am not seeing anything when I try to use beans attributes as above. However I am able to access session scoped bean used for session management of the user.

Sorry if this question is too naive. Any input to resolve the problem is greatly appreciated.

Below are my code snips. This is how I call the bean:

<h:form>
    <p:commandLink id="ajax" actionListener="#{personalBean.getPersonalInfo}" style="margin-left:5px;">  
        <h:outputText value="Personal Info" />  <br/>
    </p:commandLink>  
</h:form>

Below is the request scoped managed bean.

package com.test.model;
@ManagedBean
@Scope("request")
public class PersonalBean  implements Serializable {

private static final long serialVersionUID = 199L;
private Personal_Basic personal_Basic;
private IPersonalService personalService;

@Inject
public PersonalBean(final IPersonalService personalService) {
    this.personalService = personalService;
}
public String getPersonalInfo() {
    System.out.println("\n\nPersonalBean#getPersonalInfo called...**");
    User user = null;
    Personal_Basic personal_Basic = personalService.getPersonalBasic();
    this.setPersonal_Basic(personal_Basic);
    System.out.println("personal_Basic data:"+personal_Basic);
    System.out.println("PersonalBean#getPersonalInfo ended...");
    return "/page/personal.html";
}
// Getters/setters for class members followed
}

PersonalService implementation is annotated with @Service.

Below is the excerpt from spring configuration xml.

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:p="http://www.springframework.org/schema/p"
    xmlns:aop="http://www.springframework.org/schema/aop"
    xmlns:tx="http://www.springframework.org/schema/tx"
    xmlns:context="http://www.springframework.org/schema/context"
    xsi:schemaLocation="
       http://www.springframework.org/schema/beans
       http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
       http://www.springframework.org/schema/tx
       http://www.springframework.org/schema/tx/spring-tx-3.0.xsd
       http://www.springframework.org/schema/aop
       http://www.springframework.org/schema/aop/spring-aop-3.0.xsd
       http://www.springframework.org/schema/context
       http://www.springframework.org/schema/context/spring-context-3.0.xsd">
    <context:annotation-config/> 
    <context:component-scan base-package="com.test"/>
...................
...................
</beans>

Below is the excerpt from faces-config.xml

<?xml version="1.0"?>
<faces-config xmlns="http://java.sun.com/xml/ns/javaee"
              xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
              xsi:schemaLocation="http://java.sun.com/xml/ns/javaee     http://java.sun.com/xml/ns/javaee/web-facesconfig_2_0.xsd"
              version="2.0">
  <application>
    <el-resolver>org.springframework.web.jsf.el.SpringBeanFacesELResolver</el-resolver>
        <resource-bundle>
            <base-name>Messages</base-name>
            <var>msg</var>
        </resource-bundle>
        <locale-config>
            <default-locale>en</default-locale>
        </locale-config>
  </application>
...........................
</faces-config>

解决方案

The <context:component-scan base-package="com.test"/> element scans and registers all beans annotated with @Component, @Repository, @Service, or @Controller by default.

Spring also offers support for javax.annotation.ManagedBean (not javax.faces.bean.ManagedBean) and JSR-330 standard annotations and these are also scanned by Spring but you need to have the following dependency added to your project.

<dependency>
    <groupId>javax.inject</groupId>
    <artifactId>javax.inject</artifactId>
    <version>1</version>
</dependency>

You can see all the equivalent annotations for Spring annotations here, as you can see the equivalent of @Component is @Named and for the scope use Springs @Scope annotation instead of javax.inject.scope as mentioned. So if you want Spring to manage all the beans in your application you can use either @Component, @Named and javax.annotation.ManagedBean annotation and inject them using @Autowired or @Inject.

And to your question why beans annotated with javax.faces.bean.ManagedBean seem to be initialized but do not work is because as mentioned by @BalusC, @Inject is not supported in JSF you have to use @ManagedProperty annotation.

A little background on how it all works with Spring and JSF:

Actually there are two IOC containers in your application now with JSF and Spring, when the application starts up. First the org.springframework.web.jsf.el.SpringBeanFacesELResolver configured in your faces-config.xml delegates to the Spring root WebApplicationContext first resolving name references to Spring-defined beans, then to the default resolver of the underlying JSF implementation.

Now when the JSF bean is first looked up it is constructed and then the managed property is set via the setter method so you can inject a Spring bean using the @ManagedProperty annotation like this:

package com.test.model;
@ManagedBean
@RequestScoped
public class PersonalBean  implements Serializable {
@ManagedProperty(value="#{personalService}")
private IPersonalService personalService;
public IPersonalService getPersonalService() {
    return personalService;
}

public void setPersonalService(IPersonalService personalService) {
    this.personalService= personalService;
}

or you can also manually get the Spring bean using

org.springframework.web.context.support.WebApplicationContextUtils like this:

private Object getSpringBean(String name){
        WebApplicationContext ctx = WebApplicationContextUtils.getRequiredWebApplicationContext(
                (ServletContext) FacesContext.getCurrentInstance().getExternalContext().getContext());
        return ctx.getBean(name);
}

and use it like this:

Personal_Basic personal_Basic = ((IPersonalService) getSpringBean("personalService")).getPersonalBasic();

But instead of using two containers in your applications you can just use the Spring container to manage all your beans by annotating JSF beans with @Component and there are no implications as such that I am aware of and should be perfectly alright to use Spring annotations.

See also:

• Difference between <context:annotation-config> vs <context:component-scan>
• JSR-330 support for component detection is inconsistent
• Spring Documentation - JSF Integration
• Using Spring to Manage JSF beans

这篇关于@Scope("request")无效的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！