struts2 session,该如何处理

public static final String MESSAGE = "welcome to come struts2 world~!";    private String loginName;    private String passworld;    private Map session;      public void setSession(Map session) {                  this.session = session;              }      public String login() {        String username = loginName;        String mima = passworld;                SysuserImp sysuserImp = new SysuserImp();        // List<Sysuser> user = (List<Sysuser>) new Sysuser();        List user;        user = sysuserImp.QuerySysuser(username, mima);        if (user.size() != 0) {            Sysuser sysuser = (Sysuser) user.get(0);// 得到这个Sysuser 对像            String name=sysuser.getAdminName();            //System.out.print(name);             session.put("user", sysuser);             return this.SUCCESS;        } else {            return this.ERROR;        }    }