單應用登陸過濾器

1.流程

判斷 url 是否爲 登陸頁面，是則放行

                                         否：獲取session，存在 放行，不存在攔截

 2.   稅務系統登陸：

public class LoginFilter implements Filter {

	@Override
	public void destroy() {
	}

	@Override
	public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain chain) throws IOException, ServletException {
		HttpServletRequest request = (HttpServletRequest)servletRequest;
		HttpServletResponse response = (HttpServletResponse)servletResponse;
		String uri = request.getRequestURI();
		//判斷當前請求地址是不是登陸的請求地址
		if(!uri.contains("sys/login_")){
			//非登陸請求
			if(request.getSession().getAttribute(Constant.USER) != null){
				//說明已經登陸過
				//判斷是否訪問納稅服務系統
				if(uri.contains("/nsfw/")){
					//訪問納稅服務子系統
					User user = (User)request.getSession().getAttribute(Constant.USER);
					//獲取spring容器
					WebApplicationContext applicationContext = WebApplicationContextUtils.getWebApplicationContext(request.getSession().getServletContext());
					
					PermissionCheck pc = (PermissionCheck)applicationContext.getBean("permissionCheck");
					
					if(pc.isAccessible(user, "nsfw")){
						//說明有權限，放行
						chain.doFilter(request, response);
					} else {
						//沒有權限，跳轉到沒有權限提示頁面
						response.sendRedirect(request.getContextPath() + "/sys/login_toNoPermissionUI.action");
					}
					
				} else {
					//非訪問納稅服務子系統，則直接放行
					chain.doFilter(request, response);
				}
				
			} else {
				//沒有登陸，跳轉到登陸頁面
				response.sendRedirect(request.getContextPath() + "/sys/login_toLoginUI.action");
			}
		} else {
			//登陸請求；直接放行
			chain.doFilter(request, response);
		}
	}

	@Override
	public void init(FilterConfig arg0) throws ServletException {
	}

}

      3. 電力系統登陸攔截

public class SystemFilter implements Filter {
	
	//存放系統沒有Session，可是須要訪問的url，像這樣的鏈接須要放行
	List<String> list = new ArrayList<String>();
	/**當服務啓動的時候初始化*/
	public void init(FilterConfig config) throws ServletException {
		list.add("/index.jsp");
		list.add("/image.jsp");
		list.add("/system/elecMenuAction_menuHome.do");
		
		list.add("/error.jsp");
		list.add("/system/elecMenuAction_logout.do");
	}

	/**每次訪問URL鏈接以前，都要訪問的方法*/
	public void doFilter(ServletRequest req, ServletResponse res,
			FilterChain chain) throws IOException, ServletException {
		HttpServletRequest request = (HttpServletRequest) req;
		HttpServletResponse response = (HttpServletResponse) res;
		//記住個人代碼放置到過濾器中
		String path = request.getServletPath();
		this.forwordIndexPage(request,path);
		//若是當前訪問的鏈接是定義list中存放的鏈接，此時須要放行
		if(list.contains(path)){
			chain.doFilter(request, response);
			return;
		}
		//存在Session（不爲空）的時候要放行，Session爲空的時候，定向到首頁
		ElecUser elecUser = (ElecUser)request.getSession().getAttribute("globle_user");
		if(elecUser!=null){
			//從數據庫中查詢獲取登陸狀態
			WebApplicationContext ac = WebApplicationContextUtils.getWebApplicationContext(request.getSession().getServletContext());
			IElecUserService elecUserService = (IElecUserService)ac.getBean(IElecUserService.SERVICE_NAME);
			ElecUser user = elecUserService.findElecUserByID(elecUser);
			Long logonStateDb = user.getLogonState();
			//從Session中查詢登陸狀態
			Long logonState = elecUser.getLogonState();
			if(logonStateDb.equals(logonState)){
				chain.doFilter(request, response);
				return;
			}
			else{
				request.setAttribute("errorMsg", "您的帳號已經在異地登陸，換句話說，您被踢了！");
			}
		}
		//重定向，因爲傳遞request做用域失效
//		response.sendRedirect(request.getContextPath()+"/error.jsp");
		//轉發
		request.getRequestDispatcher("/error.jsp").forward(request, response);
	}
	
	

	/**銷燬*/
	public void destroy() {
	}

	//記住個人代碼放置到過濾器中，在跳轉到index.jsp頁面以前
	private void forwordIndexPage(HttpServletRequest request, String path) {
		if(path.equals("/index.jsp")){
			String name = "";
			String password = "";
			String checked = "";
			Cookie [] cookies = request.getCookies();
			if(cookies!=null && cookies.length>0){
				for(Cookie cookie:cookies){
					if(cookie.getName().equals("name")){
						name = cookie.getValue();
						//處理中文二進制解碼問題
						try {
							name = URLDecoder.decode(name, "UTF-8");
						} catch (UnsupportedEncodingException e) {
							e.printStackTrace();
						}
						checked = "checked";
					}
					if(cookie.getName().equals("password")){
						password = cookie.getValue();
					}
				}
			}
			request.setAttribute("name", name);
			request.setAttribute("password", password);
			request.setAttribute("checked", checked);
		}
	}
	

}

  攔截器攔截 url :

<!-- 自定義過濾器，要放置到struts2的過濾器的上面 -->
  	<filter>
  		<filter-name>SystemFilter</filter-name>
  		<filter-class>cn.itcast.elec.util.SystemFilter</filter-class>
  	</filter>
  	<filter-mapping>
  		<filter-name>SystemFilter</filter-name>
  		<url-pattern>*.jsp</url-pattern>
  		<url-pattern>*.do</url-pattern>
  	</filter-mapping>