这是我的简单例子：
Index.xhtml在根中：
<?xml version='1.0' encoding='UTF-8' ?>
<!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:h="http://java.sun.com/jsf/html">
<h:head>
<title>Title</title>
</h:head>
<h:body>
<h:form>
<h:inputText value="#{index.variable}"></h:inputText>
<h:commandButton action="#{index.submit()}" type="submit"></h:commandButton>
</h:form>
</h:body>
</html>
它的托管Bean：
import java.io.IOException;
import java.io.Serializable;
import javax.faces.bean.ManagedBean;
import javax.faces.bean.ManagedProperty;
import javax.faces.bean.ViewScoped;
import javax.faces.context.ExternalContext;
import javax.faces.context.FacesContext;
@ManagedBean
@ViewScoped
public class Index implements Serializable {
@ManagedProperty("#{sessionBean}")
private SessionBean sessionBean; /*getter&setter*/
private String variable; /*getter&setter*/
public void submit() {
sessionBean.setAsd(variable);
ExternalContext context = FacesContext.getCurrentInstance().getExternalContext();
try {
context.redirect("next");
} catch (IOException ex) {
}
}
}
/next/index.xhtml:
<?xml version='1.0' encoding='UTF-8' ?>
<!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:h="http://java.sun.com/jsf/html">
<h:head>
<title>Check variable</title>
</h:head>
<h:body>
#{sessionBean.asd}
</h:body>
</html>
SessionBean.java:
import java.io.Serializable;
import javax.faces.bean.ManagedBean;
import javax.faces.bean.SessionScoped;
@ManagedBean
@SessionScoped
public class SessionBean implements Serializable {
private String asd;
public String getAsd() {
return asd;
}
public void setAsd(String asd) {
this.asd = asd;
}
}
如果我使用 mojarra 实现，一切都会按预期工作：提交表单后，用户被重定向到root/并查看以以下形式打印的值index.xhtml.
但如果我用我的脸，asd提交现有表单后立即变为空。SessionScoped豆的行为就像RequestScoped
Why?
这是我的web.xml:
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="3.0" 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-app_3_0.xsd">
<context-param>
<param-name>javax.faces.PROJECT_STAGE</param-name>
<param-value>Development</param-value>
</context-param>
<listener>
<listener-class>org.apache.myfaces.webapp.StartupServletContextListener</listener-class>
<!--listener-class>com.sun.faces.config.ConfigureListener</listener-class-->
</listener>
<servlet>
<servlet-name>Faces Servlet</servlet-name>
<servlet-class>javax.faces.webapp.FacesServlet</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>
<welcome-file-list>
<welcome-file>index.xhtml</welcome-file>
</welcome-file-list>
<servlet-mapping>
<servlet-name>Faces Servlet</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
<session-config>
<session-timeout>
30
</session-timeout>
</session-config>
</web-app>
服务器：Apache Tomcat 7.0.34
UPDATE：如果我们改变它就可以了ViewScoped的注释Index.java bean to RequestScoped or SessionScoped。但为什么？
