Strust2-2

一、访问servelt API:

在struts1.x Action类的execute方法中，有四个参数，其中两个就是response和request。而在Struts2中，并无任何参数，所以，就不能简单地从execute方法得到HttpServletResponse或HttpServletRequest对象了。 
    但在Struts2 Action类中仍然有不少方法能够得到这些对象。下面就列出四种得到这些对象的方法。 

【方法1】使用Struts2 Aware拦截器 :

package action;  
  
import com.opensymphony.xwork2.ActionSupport;  
import javax.servlet.http.*;  
import org.apache.struts2.interceptor.*;  
  
public class MyAction extends ActionSupport implements ServletResponseAware  
{  
    private javax.servlet.http.HttpServletResponse response;  
    // 得到HttpServletResponse对象  
    public void setServletResponse(HttpServletResponse response)  
    {  
        this.response = response;  
    }      
    public String execute() throws Exception  
    {      
        response.getWriter().write("实现ServletResponseAware接口");  
    }  
}

 

【方法2】使用RequestAware拦截器 

package action;  
  
import java.util.Map;  
import org.apache.struts2.*;  
import com.opensymphony.xwork2.ActionSupport;  
import javax.servlet.http.*;  
import com.opensymphony.xwork2.util.*;  
import org.apache.struts2.interceptor.*;  
  
public class FirstAction extends ActionSupport implements RequestAware  
{  
    private Map request;  
private HttpServletResponse response;  
      
    public void setRequest(Map request)  
    {  
        this.request = request;          
    }      
    public String execute() throws Exception  
    {      
        java.util.Set<String> keys = request.keySet();  
        // 枚举全部的key值。实际上只有一个key：struts.valueStack  
        for(String key: keys)  
            System.out.println(key);  
        // 得到OgnlValueStack 对象  
        OgnlValueStack stack = (OgnlValueStack)request.get("struts.valueStack");  
        // 得到HttpServletResponse对象  
        response = (HttpServletResponse)stack.getContext().get(StrutsStatics.HTTP_RESPONSE);  
        response.getWriter().write("实现RequestAware 接口");  
    }  
}

 

方法3】使用ActionContext类 

HttpServletResponse response = (HttpServletResponse)  
  
ActionContext.getContext().get(org.apache.struts2.StrutsStatics.HTTP_RESPONSE);  
  
HttpServletRequest request = (HttpServletRequest)  
  
ActionContext.getContext().get(org.apache.struts2.StrutsStatics.HTTP_REQUEST);

 

【方法4】使用ServletActionContext类 

Struts2为咱们提供了一种最简单的方法得到HttpServletResponse及其余对象。这就是org.apache.struts2.ServletActionContext类。咱们能够直接使用ServletActionContext类的getRequest、getResponse方法来得到HttpServletRequest、HttpServletResponse对象。代码以下： 

HttpServletResponse response = ServletActionContext.getResponse()  
  
   response.getWriter().write("hello world");

 

 

一、ActionContext获取request,session,值栈。将对象压人栈顶：获取值栈，push。<s:属性>:是OGNL,获取栈顶的对象。

二、<result type="json" name="users">
     <param name="root">names</param>
   </result>

三、（1）、 request.setAttribute("s004po", s004po);

                   主题：${s004po.ma002}<br>
                   内容：${s004po.ma003}

        （2）、List<Map<String, Object>> replyList

                   request.setAttribute("replyList", replyList);

                   <s:iterator value="#request.replyList" id="column"> 
                             <s:iterator value="#column" id="map">    
                                      key: <s:property value="#map.key"/>      
                                       value: <s:property value="#map.value"/>  <br>    
                               </s:iterator>
                 </s:iterator>

四、hidden标签中的value我在js脚本中取得hidden中value时为何获得的是<s:property value="#session.LOGIN_USER"/>，我用<s:textfield value="<s:property value='#session.LOGIN_USER'/>"/>测试时在文本框中的显示也是<s:property value="#session.LOGIN_USER"/>，求教…………

解答：

<s:hidden>标签的value属性的类型是String类型，因此把<s:property value="#session.LOGIN_USER"/>当成是字符串，若是要获取值栈中的数据要用
<s:hidden name="loginUser" id="loginUser" value="%{#session.LOGIN_USER}"/>

5.Struts2文件上传路径的详细解释

http://lj6684.iteye.com/blog/1002279

Struts2文件上传原理及示例

http://blog.sina.com.cn/s/blog_87720b870100zkn2.html

struts2上传文件问题汇总

http://jingyan.baidu.com/article/acf728fd1222d8f8e510a38e.html

 

 

http://localhost:8080/YunVideo/pda/pdaLogin
http://localhost:8080/YunVideo/pda/pdaRegister

<action name="pda*" class="com.hw.hwsafe.pda.action.PdaUserAction" method="pda{1}">
 <result type="json"></result>
</action>

 public void pdaRegister() throws Exception {      response.setContentType("text/html");   response.setCharacterEncoding("UTF-8");      PrintWriter out = null;      out = response.getWriter();   out.write("注册");   out.flush();   out.close();  }  public void pdaLogin() throws Exception {   response.setContentType("text/html");   response.setCharacterEncoding("UTF-8");      PrintWriter out = null;      out = response.getWriter();   out.write("登陆");   out.flush();   out.close(); }