Struts2框架的传值问题

从后台获取数据

1. get传值【确保action类中有getter（）方法】
2. ActionContext对象传值
   a.获取session对象并调用：
   ActionContext.getContext().getSession（）.put(key,value)；
   b.获取request对象：

Map<String,object> request = ActionContext.getContext().get("request");
   request.put(key,value);

3.ServletActionContext对象传值【是ActionContext的子类】

  ServletActionContext.getRequest().setAttribute(key,value);  

4 .直接访问servlet对象【request】——实现ServletRequestWare接口

public class LoginAction implements Action,ServletRequestAware{
private String userName;
private String passWord;
**private HttpServletRequest request;**

public HttpServletRequest getRequest() {
    return request;
}
public void setRequest(HttpServletRequest request) {
    this.request = request;
}
......