如何在 JSF 的会话范围内获取和设置对象? [英] How do I get and set an object in session scope in JSF?

问题描述

我只需要在 JSF 应用程序的会话范围内保留一个对象.我在哪里定义会话变量，以及如何从视图文件或支持 bean 获取和设置它?

I need to persist just one object in session scope of my JSF application. Where do I define a session variable, and how do I get and set it from either a view file or backing bean?

推荐答案

两种通用方式:

• 将其存储在 ExternalContext#getSessionMap()

ExternalContext externalContext = FacesContext.getCurrentInstance().getExternalContext();
Map<String, Object> sessionMap = externalContext.getSessionMap();
sessionMap.put("somekey", yourVariable);

然后:

SomeObject yourVariable = (SomeObject) sessionMap.get("somekey");

或者，将其设为 @SessionScoped bean 的属性，您将其注入 @RequestScoped bean.

Or, make it a property of a @SessionScoped bean which you inject in your @RequestScoped bean.

sessionBean.setSomeVariable(yourVariable);

然后:

SomeObject yourVariable = sessionBean.getSomeVariable();

您可以通过@Inject 将@Named @SessionScoped 转化为@Named @RequestScoped.

You can get a @Named @SessionScoped into a @Named @RequestScoped via @Inject.

@Inject
private SessionBean sessionBean;

或者，如果您还没有使用 CDI，您可以通过 @ManagedProperty 将 @ManagedBean @SessionScoped 转换为 @ManagedBean @RequestScoped代码>.

Or, if you're not using CDI yet, you can get a @ManagedBean @SessionScoped into a @ManagedBean @RequestScoped via @ManagedProperty.

@ManagedProperty("#{sessionBean}")
private SessionBean sessionBean; // +getter+setter

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