4-2 用户登陆接口与界面开发

1、登陆 Controller

@Controller
public class UserController {
	
	@Autowired
	private SysUserService sysUserService;

	@RequestMapping("/login")
	public void login(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException {
		String username = request.getParameter("username");
		String password = request.getParameter("password");

		SysUser sysUser = sysUserService.findByKeyword(username);
		String errorMsg = "";

		if (StringUtils.isBlank(username)) {
                    errorMsg = "用户名不可以为空";
                } else if (StringUtils.isBlank(password)) {
                    errorMsg = "密码不可以为空";
                } else if (sysUser == null) {
                    errorMsg = "查询不到指定的用户";
                } else if (!sysUser.getPassword().equals(MD5Util.encrypt(password))) {
                    errorMsg = "用户名或密码错误";
                } else if (sysUser.getStasus() != 1) {
                    errorMsg = "用户已被冻结，请联系管理员";
                } else {
                    // login success
                    request.getSession().setAttribute("user", sysUser);
                    response.sendRedirect("/admin/index");
                    return;	// 防止提交后再次转向           
                }
		
		request.setAttribute("error", errorMsg);
                request.setAttribute("username", username);
        
                String path = "/test/signin";
                request.getRequestDispatcher(path).forward(request, response);
	}
}@Controller
public class