DAO层和Service层访问session

多情况下，我们需要在DAO或者Service层拿到Session中的值，比如下面这个应用，session中存放了当前用户的账号，在DAO层中需要insert一条record，这条record需要记录当前用户（该记录是由谁创建的），对于这样的应用，我们一般可以在Action层中通过request拿到session里的用户账号，然后传入service,再传入DAO层，就可以解决了。

    今天，我在这里记录一种方式，利用ThreadLocal来存入sesion,然后可以在任何业务层，DAO层获取Session的方式，首先建立一个CSession来存放session的值，只放了2个属性，用户的账号和姓名

Java代码 public class CSession {      private String username;      private String userId;                public String getUsername() {          return username;      }      public void setUsername(String username) {          this.username = username;      }            public String getUserId() {          return userId;      }      public void setUserId(String userId) {          this.userId = userId;      }  }  public class CSession { private String username; private String userId; public String getUsername() { return username; } public void setUsername(String username) { this.username = username; } public String getUserId() { return userId; } public void setUserId(String userId) { this.userId = userId; } }

建立SessionUser类，用来存放在整个运行期CSession的存在

Java代码 public class SessionUser {          @SuppressWarnings("unchecked")      static ThreadLocal sessionUser = new ThreadLocal();            @SuppressWarnings("unchecked")      public static void setSessionUser(CSession cSession) {          sessionUser.set(cSession);      }            public static CSession getSessionUser(){          return (CSession )sessionUser.get();      }            public static String getSessionUserId(){          return getSessionUser().getUserId();      }            public static String getSessionUserName(){          return getSessionUser().getUsername();      }  }  public class SessionUser { @SuppressWarnings("unchecked") static ThreadLocal sessionUser = new ThreadLocal(); @SuppressWarnings("unchecked") public static void setSessionUser(CSession cSession) { sessionUser.set(cSession); } public static CSession getSessionUser(){ return (CSession )sessionUser.get(); } public static String getSessionUserId(){ return getSessionUser().getUserId(); } public static String getSessionUserName(){ return getSessionUser().getUsername(); } }

在登录的Action里，登录成功后，加Session里的用户信息，放入CSession中，

Java代码 HttpSession session = request.getSession(true);  CSession cs = new CSession();  cs.setUserId(userId);  cs.setUsername(userName);  session.setAttribute("C_SESSION",cs);  HttpSession session = request.getSession(true); CSession cs = new CSession(); cs.setUserId(userId); cs.setUsername(userName); session.setAttribute("C_SESSION",cs);

最后，在session check的Filter中，把CSession注入到SessionUser中，

Java代码 public void doFilter(ServletRequest request, ServletResponse response,              FilterChain chain) throws IOException, ServletException {                    HttpServletRequest hrequest = (HttpServletRequest) request;          HttpServletResponse hresponse = (HttpServletResponse) response;                           .......                    CSession cs = (CSession) hrequest.getSession(true).getAttribute("C_SESSION");                    SessionUser.setSessionUser(cs);                                            .......      }  public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException { HttpServletRequest hrequest = (HttpServletRequest) request; HttpServletResponse hresponse = (HttpServletResponse) response; ....... CSession cs = (CSession) hrequest.getSession(true).getAttribute("C_SESSION"); SessionUser.setSessionUser(cs); ....... }

下面我们就可以再DAO层中直接从SessionUser中获取 userid 和 username,

Java代码 xxxTO.setUserId(SessionUser.getSessionUserId());  xxxTO.setUserName(SessionUser.getSessionUserName());  xxxTO.setUserId(SessionUser.getSessionUserId()); xxxTO.setUserName(SessionUser.getSessionUserName());

页面上，

Java代码 <bean:write name="C_SESSION" property="username"/>  <bean:write name="C_SESSION" property="userId"/>  <bean:write name="C_SESSION" property="username"/> <bean:write name="C_SESSION" property="userId"/>

转载于:https://www.cnblogs.com/dandre/p/4507078.html

相关资源：数据结构—成绩单生成器