java Spring MVC 获取当前登录用户
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Spring MVC get current logged in user
提问by user1555190
My app only allows access if the current user is a specific type, this also means the role they have can log into other applications and then access certain parts of my app with specific roles, for example, my web app is configured that
我的应用程序仅在当前用户是特定类型时才允许访问，这也意味着他们拥有的角色可以登录其他应用程序，然后以特定角色访问我的应用程序的某些部分，例如，我的 Web 应用程序配置为
<security-role>
<role-name>teamb</role-name>
</security-role>
Now what I need is to be able access the details regarding this role in my app, ie.e user name
现在我需要的是能够在我的应用程序中访问有关此角色的详细信息，即用户名
how can I do this in my Spring MVCapp?
我怎样才能在我的Spring MVC应用程序中做到这一点？
回答by Fritz
First of all, include the corresponding tag library in your pages (I'll make an example using JSP)
首先，在你的页面中包含相应的标签库（我会用JSP做一个例子）
<%@ taglib prefix="sec" uri="http://www.springframework.org/security/tags" %>
Then you just have to use those tags to query for permissions and of course, the data.
然后你只需要使用这些标签来查询权限，当然还有数据。
To see if an user has enough privileges for something:
要查看用户是否具有足够的权限，请执行以下操作：
<sec:authorize ifAllGranted="ROLE_ADMIN">
<a href="page.htm">Some Admin Stuff</a>
</sec:authorize>
If the user has enough privileges, the link to page.htmwill be rendered.
如果用户有足够的权限，链接page.htm将被呈现。
To get the username use ${SPRING_SECURITY_LAST_USERNAME}. Here's a logout link as an example:
要获取用户名，请使用${SPRING_SECURITY_LAST_USERNAME}. 这是一个注销链接作为示例：
<a href="<c:url value="/j_spring_security_logout" />">Logout <c:out value="${SPRING_SECURITY_LAST_USERNAME}"/></a>
Edit
编辑
To query the currently authenticated user you can try different approaches:
要查询当前经过身份验证的用户，您可以尝试不同的方法：
Authentication authentication = SecurityContextHolder.getContext().getAuthentication();
String username = authentication.getName();
or
或者
Authentication authentication = SecurityContextHolder.getContext().getAuthentication();
User user = (User)authentication.getPrincipal();
user.getUsername();
Just remember to check if authenticationis not null before invoking the getNameor getPrincipalmethods.
请记住authentication在调用getNameorgetPrincipal方法之前检查是否为空。
