@SessionScoped来自javax.enterprise.context.SessionScoped

此选项仅与CDI @Named结合使用.使用JSF时 @ManagedBean ，则应该改用javax.faces.bean包中的范围注释.

This one works in combination with CDI @Named only. As you're using JSF @ManagedBean, you should be using the scope annotations from javax.faces.bean package instead.

import javax.faces.bean.ManagedBean;
import javax.faces.bean.SessionScoped;

@ManagedBean
@SessionScoped
public class AppManager implements Serializable {

在没有有效范围的情况下，JSF托管bean的行为类似于

Without a valid scope, a JSF managed bean would behave like @RequestScoped which effectively means that it's constructed again and again on every request.