@JSF 2.2中@PostConstruct之后的ManagedProperty null
我的规格：@JSF 2.2中@PostConstruct之后的ManagedProperty null,jsf,jsf-2,glassfish,Jsf,Jsf 2,Glassfish,我的规格： 动态Web模块3.1 GlassFish Web Extensions 4.0 Java 1.8 JavaScript 1.0 JavaServerFaces2.2 服务器：glassfish-4.1.1 OS:赢10分 IDE：版本：Neon.2发行版（4.6.2） 请注意，我已经研究了这个话题，并找到了几个相关的帖子 e、 g 但这两个建议的解决方案都不适合我，也不适用于我的情况。 我不会混合使用CDI和/或JSF和/或Spring。它只是JSF2.2注释 我注入@Man
- 动态Web模块3.1
- GlassFish Web Extensions 4.0
- Java 1.8
- JavaScript 1.0
- JavaServerFaces2.2
- 服务器：glassfish-4.1.1
- OS:赢10分
- IDE：版本：Neon.2发行版（4.6.2）
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:ui="http://xmlns.jcp.org/jsf/facelets"
xmlns:h="http://xmlns.jcp.org/jsf/html"
xmlns:f="http://xmlns.jcp.org/jsf/core">
<h:head>
<title>Title</title>
</h:head>
<h:body>
<h3><h:outputText value="#{country.name}" /> </h3>
<h:form>
<h:commandButton
id="changeCountryNameBtn"
value="Change"
action="result"
actionListener="#{appBean.changeCountryName}"
/>
</h:form>
</h:body>
</html>
package com.test.beans;
import javax.faces.application.Application;
import javax.faces.bean.ManagedBean;
import javax.faces.bean.SessionScoped;
import javax.faces.context.FacesContext;
import javax.faces.event.ActionEvent;
@ManagedBean
@SessionScoped
public class AppBean {
public void changeCountryName(ActionEvent ev) {
FacesContext context = FacesContext.getCurrentInstance();
Application app = context.getApplication();
app.publishEvent(context, ChangeCountrySystemEvent.class, ev.getSource());
System.out.println(">>>> AppBean.publishEvent(ChangeCountrySystemEvent) fired... " + ev.getSource());
}
}
package com.test.beans;
import javax.faces.event.SystemEvent;
public class ChangeCountrySystemEvent extends SystemEvent {
private static final long serialVersionUID = -1587717461942271611L;
public ChangeCountrySystemEvent(Object source) {
super(source);
System.out.println(">>>> ChangeCountrySystemEvent.class :: constructor invoked!");
}
}
2017-04-02T21:49:51.392-0300|Info: JSF_TestProject was successfully deployed in 579 milliseconds.
2017-04-02T21:49:52.251-0300|Info: >>>> Country constructor called...
2017-04-02T21:49:52.277-0300|Info: >>>> ChangeCountrySystemEventListener.class :: Listener constructor invoked!!!
2017-04-02T21:49:52.277-0300|Info: >>>> Country.class :: app.subscribeToEvent() called...
2017-04-02T21:50:16.572-0300|Info: >>>> ChangeCountrySystemEvent.class :: constructor invoked!
2017-04-02T21:50:16.572-0300|Info: >>>> ChangeCountrySystemEventListener.class :: processEvent() > country managed property is EMPTY !!!!
2017-04-02T21:50:16.572-0300|Info: >>>> AppBean.publishEvent(ChangeCountrySystemEvent) fired... javax.faces.component.html.HtmlCommandButton@424c250c
package com.test.beans;
import javax.faces.bean.ManagedProperty;
import javax.faces.context.FacesContext;
import javax.faces.event.SystemEvent;
import javax.faces.event.SystemEventListener;
public class ChangeCountrySystemEventListener implements SystemEventListener {
@ManagedProperty("#{country}")
Country country;
// getters and setters
public Country getCountry() {
return country;
}
public void setCountry(Country country) {
this.country = country;
}
public ChangeCountrySystemEventListener(FacesContext fc) {
super();
System.out.println(">>>> ChangeCountrySystemEventListener.class :: Listener constructor invoked!!!");
}
@Override
public void processEvent(SystemEvent se) {
if (country != null) {
country.setName("Sweden");
System.out.println(">>>> ChangeCountrySystemEventListener.class :: SYSTEM EVENT PROCESSED... <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< ");
} else if (country == null) {
System.out.println(">>>> ChangeCountrySystemEventListener.class :: processEvent() > country managed property is EMPTY !!!!");
}
}
@Override
public boolean isListenerForSource(Object source) {
return true; // needs to be set to true, otherwise "processEvent" won't be called...
}
}
package com.test.beans;
import javax.annotation.PostConstruct;
import javax.faces.application.Application;
import javax.faces.bean.ManagedBean;
import javax.faces.bean.SessionScoped;
import javax.faces.context.FacesContext;
@ManagedBean(name = "country", eager = true)
@SessionScoped
public class Country {
private String name = "Norway";
public Country() {
System.out.println(">>>> Country constructor called...");
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
@PostConstruct
public void init() {
FacesContext fc = FacesContext.getCurrentInstance();
Application app = fc.getApplication();
app.subscribeToEvent(ChangeCountrySystemEvent.class, new ChangeCountrySystemEventListener(fc));
System.out.println(">>>> Country.class :: app.subscribeToEvent() called... ");
}
}
package com.test.beans;
import javax.faces.application.Application;
import javax.faces.bean.ManagedBean;
import javax.faces.bean.SessionScoped;
import javax.faces.context.FacesContext;
import javax.faces.event.ActionEvent;
@ManagedBean
@SessionScoped
public class AppBean {
public void changeCountryName(ActionEvent ev) {
FacesContext context = FacesContext.getCurrentInstance();
Application app = context.getApplication();
app.publishEvent(context, ChangeCountrySystemEvent.class, ev.getSource());
System.out.println(">>>> AppBean.publishEvent(ChangeCountrySystemEvent) fired... " + ev.getSource());
}
}
package com.test.beans;
import javax.faces.event.SystemEvent;
public class ChangeCountrySystemEvent extends SystemEvent {
private static final long serialVersionUID = -1587717461942271611L;
public ChangeCountrySystemEvent(Object source) {
super(source);
System.out.println(">>>> ChangeCountrySystemEvent.class :: constructor invoked!");
}
}
2017-04-02T21:49:51.392-0300|Info: JSF_TestProject was successfully deployed in 579 milliseconds.
2017-04-02T21:49:52.251-0300|Info: >>>> Country constructor called...
2017-04-02T21:49:52.277-0300|Info: >>>> ChangeCountrySystemEventListener.class :: Listener constructor invoked!!!
2017-04-02T21:49:52.277-0300|Info: >>>> Country.class :: app.subscribeToEvent() called...
2017-04-02T21:50:16.572-0300|Info: >>>> ChangeCountrySystemEvent.class :: constructor invoked!
2017-04-02T21:50:16.572-0300|Info: >>>> ChangeCountrySystemEventListener.class :: processEvent() > country managed property is EMPTY !!!!
2017-04-02T21:50:16.572-0300|Info: >>>> AppBean.publishEvent(ChangeCountrySystemEvent) fired... javax.faces.component.html.HtmlCommandButton@424c250c
ManagedProperty可用于带有ManagedBean注释的类的字段，以将值注入该属性 如果此注释出现在没有ManagedBean注释的类上，则实现不得对此注释执行任何操作 请看
由于ChangeCountrySystemEventListener类未使用ManagedBean进行注释，因此不会对ManagedProperty字段country及其null采取任何操作。感谢您的回复。不幸的是，添加ManagedBean注释（甚至SessionScoped）并不能解决这个问题。即使所有四个类（AppBean、ChangeCountrySystemEvent、ChangeCountrySystemEventListener、Country）都用ManagedBean注释，问题仍然存在。请在侦听器中使用以下代码访问国家管理的bean.Country=（Country）FacesContext.getCurrentInstance（）.getExternalContext（）.getSessionMap（）.get（“国家”）；非常感谢。你提出的解决方案对我有效。：）