spring security中当前用户信息

1：如果在jsp页面中获取可以使用spring security的标签库

在页面中引入标签

1	<%@ taglib prefix="sec" uri="http://www.springframework.org/security/tags" %>

然后：

1	<div> username : <sec:authentication property="name"/></div>

2：如果要在程序中获得

看了网上很多写法都是在程序中写这样的代码

1	UserDetails userDetails = (UserDetails) SecurityContextHolder.getContext().getAuthentication() .getPrincipal();

但我在实际运用中发现获得的Authentication为null。仔细看了下源代码发现，如果想用上面的代码获得当前用户，必须在spring

security过滤器执行中执行，否则在过滤链执行完时org.springframework.security.web.context.SecurityContextPersistenceFilter类会

调用SecurityContextHolder.clearContext();而把SecurityContextHolder清空，所以会得到null。经过spring security认证后，

security会把一个SecurityContextImpl对象存储到session中，此对象中有当前用户的各种资料

SecurityContextImpl securityContextImpl = (SecurityContextImpl) request

.getSession().getAttribute("SPRING_SECURITY_CONTEXT");

// 登录名

System.out.println("Username:"

+ securityContextImpl.getAuthentication().getName());

// 登录密码，未加密的

System.out.println("Credentials:"

+ securityContextImpl.getAuthentication().getCredentials());

WebAuthenticationDetails details = (WebAuthenticationDetails) securityContextImpl

.getAuthentication().getDetails();

// 获得访问地址

System.out.println("RemoteAddress" + details.getRemoteAddress());

// 获得sessionid

System.out.println("SessionId" + details.getSessionId());

// 获得当前用户所拥有的权限

List<GrantedAuthority> authorities = (List<GrantedAuthority>) securityContextImpl

.getAuthentication().getAuthorities();

for (GrantedAuthority grantedAuthority : authorities) {

System.out.println("Authority" + grantedAuthority.getAuthority());

}