亚洲天堂中文字幕,亚洲av综合日韩,亚洲AV一宅男色影视

[原]Struts2-深入探索

[標題]:[原]Struts2-深入探索
[時間]:2009-8-26
[摘要]:Struts2中一些零碎的知識點:struts.xml詳解、模型驅動、Preparable接口、防止表單重復提交、ActionContext、動態方法調用、異常
[關鍵字]:浪曦視頻，Struts2應用開發系列，WebWork，Apache，深入探索
[環境]:struts-2.1.6、JDK6、MyEclipse7、Tomcat6
[作者]:Winty (wintys@gmail.com) http://www.tkk7.com/wintys

[正文]:
1、struts.xml詳解
a. struts.properties
    在struts.xml中可以定義constant覆蓋struts-core.jar/org/apache/struts2/default.properties中的設置。
    例:<constant name="struts.custom.i18n.resources" value="message"/>

   也可以直接新建struts.properties(與struts.xml在同一目錄)，在struts.properties中配置。推薦在struts.properties中進行配置。
   例:struts.custom.i18n.resources = message

b. abstract package
   struts-core.jar/struts-default.xml，中有如下定義。
   <package name="struts-default" abstract="true">
       ......
   </package>
   其中abstract="true"中，表示在此package中不能定義Action(與Java abstract類相似)，僅供繼承。

c. namespace
   strut.xml中:
   <package name="MyStruts" extends="struts-default" namespace="/mystruts">
   ......
   </package>

   默認命名空間為namespace=""，命名空間要以"/"開頭。
   JSP訪問:<s:form action="miscellaneous" namespace="/mystruts">。
   不能寫成<s:form action="/mystruts/miscellaneous"> ，否則會發生錯誤:"No configuration found for the specified action: '/mystruts/miscellaneous' in namespace: '/miscellaneous'. Form action defaulting to 'action' attribute's literal value."[2]。

d. 模塊化配置
   ......
   <struts>
       <include file="struts1.xml" />
       <package ...>
           ......
       </package>
   </struts>
   include中struts1.xml的編寫與struts.xml是類似的。

2、屬性驅動與模型驅動
屬性驅動:直接在Action中寫表單屬性。

/StrutsHelloWorld/src/wintys/struts2/miscellaneous/MiscellaneousAction.java：

package wintys.struts2.miscellaneous;
import com.opensymphony.xwork2.ActionSupport;
/**
*
* @author Winty (wintys@gmail.com)
* @version 2009-8-24
* @see http://wintys.blogjava.net
*/
@SuppressWarnings("serial")
public class MiscellaneousAction extends ActionSupport {
   private String name;
   private String password;
   public String getName() {
       return name;
   }
   public void setName(String name) {
       this.name = name;
   }
   public String getPassword() {
       return password;
   }
   public void setPassword(String password) {
       this.password = password;
   }

   @Override
   public String execute() throws Exception {
       return SUCCESS;
   }
}

模型驅動:將屬性放到JavaBean中，Action需要實現com.opensymphony.xwork2.ModelDriven接口。ModelDrivenInterceptor 必須在之前StaticParametersInterceptor and ParametersInterceptor。這個順序已在defaultStack Interceptor中定義。

/StrutsHelloWorld/src/wintys/struts2/miscellaneous/User.java:

package wintys.struts2.miscellaneous;
/**
* 模型驅動Action中的模型
* @author Winty (wintys@gmail.com)
* @version 2009-8-25
* @see http://wintys.blogjava.net
*/
public class User {
   private String name;
   private String password;
   public String getName() {
       return name;
   }
   public void setName(String name) {
       this.name = name;
   }
   public String getPassword() {
       return password;
   }
   public void setPassword(String password) {
       this.password = password;
   }
}

/StrutsHelloWorld/src/wintys/struts2/miscellaneous/MiscellaneousModelDrivenAction.java:

package wintys.struts2.miscellaneous;
import com.opensymphony.xwork2.ModelDriven;

@SuppressWarnings("serial")
public class MiscellaneousModelDrivenAction extends ActionSupport implements
       ModelDriven<User>{

   private User user = new User();

   @Override
   public User getModel() {
       return user;
   }

   @Override
   public String execute() throws Exception {
       return SUCCESS;
   }
}

3、Preparable接口
Action還可以實現com.opensymphony.xwork2.Preparable接口，用于準備Action自己。Preparable中的prepare方法在Action執行其它方法前執行。

4、使用simple 主題時，如何單獨格式化Struts錯誤提示信息
單獨顯示name字段的fielderror:

<s:fielderror>
<s:param>name</s:param>
</s:fielderror>

5、Struts防止表單重復提交
   JSP頁面中加入token和actionerror:
<s:actionerror />
<s:form .../>
   <s:token />
</s:form>

   token產生的actionerror的i18n key為:struts.message.invalid.token。

   在struts.xml中的Action配置中加入token interceptor，和invalid.token result:

        <action name="miscellaneous" class="wintys.struts2.miscellaneous.MiscellaneousModelDrivenAction">
           <result name="success">/miscellaneous/output.jsp</result>
           <result name="input">/miscellaneous/input.jsp</result>

            <result name="invalid.token" >/miscellaneous/input.jsp</result>
           <interceptor-ref name="token" />
           <interceptor-ref name="defaultStack" />
        </action>

   生成的JSP頁面如下:
   <input type="hidden" name="struts.token.name" value="struts.token" />
   <input type="hidden" name="struts.token" value="ORU0RZIP8JWQ7BDZG4P1NJSEKITGG6X5" />

   struts.token.name指<s:token />中的name，默認為struts.token。也可以自己指定<s:token name="mytoken" />。則生成如下token:
   <input type="hidden" name="struts.token.name" value="mytoken" />
   <input type="hidden" name="mytoken" value="GFD13EW206G2DY9AB3SRIAVXXT1S915C" />

6、通過Struts獲取Servlet API
   一般Java Web程序不能離開容器進行測試。容器內測試常用框架:Cactus(jakarta.apache.org/cactus/index.html) 、Mock。

   通過Struts獲取Servlet API，使程序可脫離容器測試。Struts中可通過如下方法獲取Servlet API:ActionContext 、ServletActionContext、ServletXXXAware。首選ActionContext，其次選擇ServletActionContext，再次ServletXXXAware。

a. ActionContext
   com.opensymphony.xwork2.ActionContext.getActionContext()獲取ActionContext實例。

   ActionContext的get()和put()方法與HttpServletRequest的對應關系:
   ActionContext.get() <=> HttpServletRequest.getAttribute()
   ActionContext.put() <=> HttpServletRequest.setAttribute()

   例:

ActionContext context = ActionContext.getContext();
context.put("info", "this is ActionContext value");

   但是ActionContext無法獲取Servlet HttpResponse對象。

b. ServletActionContext
   org.apache.struts2.ServletActionContext是com.opensymphony.xwork2.ActionContext的子類。

   使用靜態方法直接獲取Servlet對象:
   Request: ServletActionContext.getRequest();
   Response: ServletActionContext.getResponse();
   Session: ServletActionContext.getRequest().getSession();

   例:

       Cookie cookie = new Cookie("mycookie" , "10000");
       HttpServletResponse response = ServletActionContext.getResponse();
       response.addCookie(cookie);

c. ServletXXXAware接口
   org.apache.struts2.util.ServletContextAware接口
   org.apache.struts2.interceptor.ServletRequestAware接口
   org.apache.struts2.interceptor.ServletResponseAware接口
   org.apache.struts2.interceptor.SessionAware接口

   實現ServletXXXAware接口的Action會被Struts自動注入相應的Servlet對象。

   例:

package wintys.struts2.miscellaneous;

import org.apache.struts2.interceptor.ServletRequestAware;
import com.opensymphony.xwork2.ActionSupport;

@SuppressWarnings("serial")
public class MiscellaneousModelDrivenAction extends ActionSupport implements
       ServletRequestAware {
   private HttpServletRequest request;
   ......
   @Override
   public String execute() throws Exception {
       //實現ServletRequestAware接口，Struts自動注入的request
       Cookie[] cookies = this.request.getCookies();
       for(Cookie ck : cookies){
           System.out.print("cookie:" + ck.getName());
           System.out.println(" = " + ck.getValue());
       }

       return SUCCESS;
   }
   ......
   @Override
   public void setServletRequest(HttpServletRequest request) {
       this.request = request;
   }
}

7、動態方法調用
a. Action配置中，由method指定動態調用方法的名稱。
<action name="myaction" class="com.tests.MyAction" method="myexecute">
......
</action>

b.在JSP頁面中，調用Action時加感嘆號指定動態調用方法的名稱。
<s:form action="myaction!myexecute" />

c.通配符
<action name="*action" class="com.tests.MyAction" method="{1}">
則請求中helloaction對應到action中的hello()方法，以此類推。

8、異常
發生異常時，可轉到指定的result。由exception-mapping配置

<action name="miscellaneous" class="wintys.struts2.miscellaneous.MiscellaneousModelDrivenAction">
   <result name="success">/miscellaneous/output.jsp</result>
   <result name="input">/miscellaneous/input.jsp</result>
   <exception-mapping exception="wintys.struts2.miscellaneous.NameInvalidException" result="nameInvalid" />
   <result name="nameInvalid">/miscellaneous/nameInvalidException.jsp</result>
</action>

也可以配置全局exception mapping

<global-exception-mapping>
<exception-mapping result="nameInvalid" />
</global-exception-mapping>

nameInvalidException.jsp:

<s:property value="exception"/>
<s:property value="exceptionStack" />

NameInvalidException.java:

package wintys.struts2.miscellaneous;
@SuppressWarnings("serial")
public class NameInvalidException extends Exception {
   public NameInvalidException(String message) {
       super(message);
   }
}

9、詳細代碼
/StrutsHelloWorld/WebRoot/miscellaneous/input.jsp:

<%@ page language="java" contentType="text/html;charset=UTF-8" pageEncoding="UTF-8"%>
<%@ taglib uri="/struts-tags" prefix="s" %>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
    <title>Input</title>
</head>
<body>
    <s:actionerror/>

   <s:form action="miscellaneous" method="post" theme="simple" namespace="/mystruts">
       <s:token name="mytoken"/>

       用戶名:<s:textfield name="name" />
       <s:fielderror >
           <s:param>name</s:param>
       </s:fielderror>
       <br />


       密碼:<s:textfield name="password"/>
       <s:fielderror >
           <s:param>password</s:param>
       </s:fielderror>
       <br />

       <s:submit name="提交" />
   </s:form>

   <hr />
   動態方法調用方法二:   miscellaneous!myexecute
   <s:form action="miscellaneous!myexecute" namespace="/mystruts">
       <s:token name="mytoken"/>
       <s:hidden name="name" value="test" />
       <s:hidden name="password" value="test" />
       <s:submit name="提交執行myexecute() " />
   </s:form>
</body>
</html>

/StrutsHelloWorld/WebRoot/miscellaneous/output.jsp:

/StrutsHelloWorld/src/wintys/struts2/miscellaneous/MiscellaneousModelDrivenAction.java:

package wintys.struts2.miscellaneous;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.struts2.ServletActionContext;
import org.apache.struts2.interceptor.ServletRequestAware;
import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.ActionSupport;
import com.opensymphony.xwork2.ModelDriven;
/**
* Struts2深入探索
* @author Winty (wintys@gmail.com)
* @version 2009-8-26
* @see http://wintys.blogjava.net
*/
@SuppressWarnings("serial")
public class MiscellaneousModelDrivenAction extends ActionSupport implements
       ModelDriven<User> , ServletRequestAware {

   private User user = new User();
   private HttpServletRequest request;

   @Override
   public User getModel() {
       return user;
   }

   @Override
   public String execute() throws Exception {
       System.out.println("this is model driven action");

       if(user.getName().equals("admin")){
           throw new NameInvalidException("name 'admin' is invalid");
       }

       //ActionContext.put相當于HttpServletRequest.setAttribute()
       ActionContext context = ActionContext.getContext();
       context.put("info", "this is ActionContext value");

       //ServletActionContext.getResponse得到Response對象
       Cookie cookie = new Cookie("mycookie" , "10000");
       HttpServletResponse response = ServletActionContext.getResponse();
       response.addCookie(cookie);

       //實現ServletRequestAware接口，Struts自動注入的request
       Cookie[] cookies = this.request.getCookies();
       for(Cookie ck : cookies){
           System.out.print("cookie:" + ck.getName());
           System.out.println(" = " + ck.getValue());
       }

       return SUCCESS;
   }

   public String myexecute()throws Exception{
       System.out.println("myexecute()");

       return SUCCESS;
   }

   @Override
   public void validate() {
       if(user.getName() == null || user.getName().equals("")){
           this.addFieldError("name", "invalid name");
       }
   }

   @Override
   public void setServletRequest(HttpServletRequest request) {
       this.request = request;
   }
}

/src/struts.xml:

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC
    "-//Apache Software Foundation//DTD Struts Configuration 2.0//EN"
    "http://struts.apache.org/dtds/struts-2.0.dtd">

<struts>
    <package name="MyStruts" extends="struts-default" namespace="/mystruts">
        
        <action name="miscellaneous" class="wintys.struts2.miscellaneous.MiscellaneousModelDrivenAction">
           <result name="success">/miscellaneous/output.jsp</result>
           <result name="input">/miscellaneous/input.jsp</result>
           <exception-mapping exception="wintys.struts2.miscellaneous.NameInvalidException" result="nameInvalid" />
           <result name="nameInvalid">/miscellaneous/nameInvalidException.jsp</result>
           <result name="invalid.token" >/miscellaneous/input.jsp</result>
           <interceptor-ref name="token" />
           <interceptor-ref name="defaultStack" />
        </action>
    </package>
</struts>

[參考資料]:
    [1]《浪曦視頻之Struts2應用開發系列》
   [2] No configuration found for the specified action : http://javasunnyboy.javaeye.com/blog/254753

[附件]:
    源代碼 : http://www.tkk7.com/Files/wintys/struts_miscellaneous.zip

posted on 2009-08-29 20:32 天堂露珠閱讀(916) 評論(0) 編輯收藏所屬分類: Struts

常用鏈接

訂閱

留言簿(7)

隨筆分類(130)

隨筆檔案(123)

搜索

積分與排名

最新評論


只有注冊用戶登錄后才能發表評論。




網站導航: 博客園 IT新聞 Chat2DB C++博客博問管理
相關文章: [原]Struts2-整合JFreeChart [原]Struts2-深入探索 [原]Struts2-國際化 [原]Struts2-文件上傳與下載 [原]Struts2-攔截器 [原]Struts2校驗框架 [原]Struts2輸入校驗 [原]Struts2類型轉換 [原]Struts2-入門與配置 [轉]Struts2.1.6 - Unable to load configuration