【奇怪】Struts2 不能获取客户端【一部分】字段

public class Employee implements java.io.Serializable {    // Fields    private static final long serialVersionUID = 5106663630382037556L;    private String sn;    private Position position;    private Department department;    private String password;    private String name;    private String status;    // Constructors    /** default constructor */    public Employee() {    }    // Property accessors    /**     * @return 工号     */    public String getSn() {        return this.sn;    }    public void setSn(String sn) {        this.sn = sn;    }    /**     * @return 职务     */    public Position getPosition() {        return this.position;    }    public void setPosition(Position position) {        this.position = position;    }    /**     * @return 部门     */    public Department getDepartment() {        return this.department;    }    public void setDepartment(Department department) {        this.department = department;    }        /**     * @return 密码     */    public String getPassword() {        return this.password;    }    public void setPassword(String password) {        this.password = password;    }        /**     * @return 姓名     */    public String getName() {        return this.name;    }    public void setName(String name) {        this.name = name;    }        /**     * @return 状态     */    public String getStatus() {        return this.status;    }    public void setStatus(String status) {        this.status = status;    }}

/** * 用户登录action * @author 北大青鸟 * @version 1.0 */public class UserAction extends ActionSupport {    private static final long serialVersionUID = 1L;    private final Log logger = LogFactory.getLog(getClass());    private Employee employee;    private EmployeeService employeeService;    /**     * 用户登录。     * @return     * @throws Exception     */    public String login() throws Exception {        Employee newEmployee = null;        try {            System.out.println(employee.getName());            employee.setPassword(new MD5(employee.getPassword()).compute());            newEmployee = employeeService.login(employee);            if (logger.isDebugEnabled()) {                logger.debug("---------------" + newEmployee.getName());            }        } catch (Exception e) {            e.printStackTrace();            logger.error(e.getMessage());        }        String ret = INPUT;        if (newEmployee == null) {            ret = INPUT;        } else {            ActionContext ac = ActionContext.getContext();            ac.getSession().put("employee", newEmployee);            //获取职员职务信息，并获得职务名称            String nameCn = newEmployee.getPosition().getNameCn();            if ("员工".equals(nameCn)) {                ret = "staff";                ClaimVoucher claimVoucher = new ClaimVoucher();                claimVoucher.setStatus(Constants.CLAIMVOUCHER_CREATED);                claimVoucher.setId(0);                ac.getSession().put("claimVoucher", claimVoucher);            } else if ("部门经理".equals(nameCn)) {                ret = "deptManager";            } else if ("总经理".equals(nameCn)) {                ret = "manager";            } else if ("财务".equals(nameCn)) {                ret = "cashier";            }        }        return ret;    }       //其他get/set方法省略}