Spring Security-获取当前登录用户的详细信息

在Spring框架里面，可以通过以下几种方式获取到当前登录用户的详细信息：

1. 在Bean中获取用户信息

Authentication authentication = SecurityContextHolder.getContext().getAuthentication();
if (!(authentication instanceof AnonymousAuthenticationToken)) {
    String currentUserName = authentication.getName();
    return currentUserName;
}

Spring Security框架提供了多种AuthenticationToken的派生类，根据自己的应用场景，可以对SecurityContextHolder里面的AuthenticationToken进行类型转换，如下：

UsernamePasswordAuthenticationToken authenticationToken = (UsernamePasswordAuthenticationToken) SecurityContextHolder.getContext().getAuthentication();
//details里面可能存放了当前登录用户的详细信息，也可以通过cast后拿到
User userDetails = (User) authenticationToken.getDetails();

PS. AuthenticationToken的类型转换同样适用于下面提到的Principal类。

2. 在Controller中获取用户信息

1.通过Principal参数获取：

import java.security.Principal;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.ResponseBody;

@Controller
public class SecurityController {

    @RequestMapping(value = "/username", method = RequestMethod.GET)
    @ResponseBody
    public String currentUserName(Principal principal) {
        return principal.getName();
    }
}

2.通过Authentication参数获取：

import org.springframework.security.core.Authentication;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.ResponseBody;

@Controller
public class SecurityController {

    @RequestMapping(value = "/username", method = RequestMethod.GET)
    @ResponseBody
    public String currentUserName(Authentication authentication) {
        return authentication.getName();
    }
}

3.通过HttpServletRequest获取

import java.security.Principal;
import javax.servlet.http.HttpServletRequest;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.ResponseBody;

@Controller
public class SecurityController {

    @RequestMapping(value = "/username", method = RequestMethod.GET)
    @ResponseBody
    public String currentUserNameSimple(HttpServletRequest request) {
        Principal principal = request.getUserPrincipal();
        return principal.getName();
    }
}

3. 通过Interface获取用户信息

通过Interface获取其实和第一种在Bean中获取用户信息是一样的，都是访问SecurityContextHolder获取的，只是进行了封装。

public interface IAuthenticationFacade {
    Authentication getAuthentication();
}
@Component
public class AuthenticationFacade implements IAuthenticationFacade {

    @Override
    public Authentication getAuthentication() {
        return SecurityContextHolder.getContext().getAuthentication();
    }
}

下面是使用方法：

@Controller
public class SecurityController {
    @Autowired
    private IAuthenticationFacade authenticationFacade;

    @RequestMapping(value = "/username", method = RequestMethod.GET)
    @ResponseBody
    public String currentUserNameSimple() {
        Authentication authentication = authenticationFacade.getAuthentication();
        return authentication.getName();
    }
}