struts2访问web元素方法

骑猪看日落 2022-08-13 12:49 155阅读 0赞

Struts2中访问web元素的四种方式及前台jsp页面获取后台值的方式

四种方式：

1. 通过ActionContext来访问request,session,application对象

2. 通过实现RequestAware、SessionAware、ApplicationAware接口来访问request,session,application对象

3. 通过ServletActionContext来访问request,session,application对象

4. 通过实现ServletRequestAware接口来访问request,session,application对象

演示代码：

方式一：

Java代码  [![复制代码][icon_copy.gif]][icon_copy.gif 1]

1.  /\*\*
2.  \* 通过ActionContext来访问request,session,application对象
3.  \* @author 健
4.  \*/ 
5.  **public** **class** UserAction1 **extends** ActionSupport\{ 
6.      /\*\*
7.       \* 序列化
8.       \*/ 
9.      **private** **static** **final** **long** serialVersionUID = 1L; 
10.     /\*\*
11.      \* request
12.      \*/ 
13.     **private** Map <String,Object>request; 
14.     /\*\*
15.      \* response
16.      \*/ 
17.     **private** Map <String,Object>session; 
18.     /\*\*
19.      \* application
20.      \*/ 
21.     **private** Map <String,Object>application; 
22.     /\*\*
23.      \* 添加用户
24.      \* @return 用户是否添加成功
25.      \*/ 
26.     @SuppressWarnings("unchecked") 
27.     @Override 
28.     **public** String execute()\{ 
29.         System.out.println("通过ActionContext来访问request,session,application对象"); 
30.         // 初始化 
31.         request = (Map<String,Object>)ActionContext.getContext().get("request"); 
32.         session = ActionContext.getContext().getSession(); 
33.         application = ActionContext.getContext().getApplication(); 
34.         // 赋值 
35.         request.put("requestKey", "requestValue"); 
36.         session.put("sessionKey", "sessionValue"); 
37.         application.put("applicationKey", "applicationValue"); 
38.         **return** "success"; 
39.     \} 
40. \}

**\[java\]**  [view plain][] [copy][view plain]

1.  /\*\* 
2.   \* 通过ActionContext来访问request,session,application对象 
3.   \* @author 健 
4.   \*/  
5.  **public** **class** UserAction1 **extends** ActionSupport\{  
6.      /\*\* 
7.       \* 序列化 
8.       \*/  
9.      **private** **static** **final** **long** serialVersionUID = 1L;  
10.     /\*\* 
11.      \* request 
12.      \*/  
13.     **private** Map <String,Object>request;  
14.     /\*\* 
15.      \* response 
16.      \*/  
17.     **private** Map <String,Object>session;  
18.     /\*\* 
19.      \* application 
20.      \*/  
21.     **private** Map <String,Object>application;  
22.     /\*\* 
23.      \* 添加用户  
24.      \* @return 用户是否添加成功 
25.      \*/  
26.     @SuppressWarnings("unchecked")  
27.     @Override  
28.     **public** String execute()\{  
29.         System.out.println("通过ActionContext来访问request,session,application对象");  
30.         // 初始化  
31.         request = (Map<String,Object>)ActionContext.getContext().get("request");  
32.         session = ActionContext.getContext().getSession();  
33.         application = ActionContext.getContext().getApplication();  
34.         // 赋值  
35.         request.put("requestKey", "requestValue");  
36.         session.put("sessionKey", "sessionValue");  
37.         application.put("applicationKey", "applicationValue");  
38.         **return** "success";  
39.     \}  
40. \}

方式二：

Java代码  [![复制代码][icon_copy.gif]][icon_copy.gif 1]

1.  /\*\*
2.  \* 通过实现RequestAware、SessionAware、ApplicationAware接口来访问request,session,application对象
3.  \* @author 健
4.  \*/ 
5.  **public** **class** UserAction2 **extends** ActionSupport **implements** RequestAware,SessionAware,ApplicationAware\{ 
6.      /\*\*
7.       \* 序列化
8.       \*/ 
9.      **private** **static** **final** **long** serialVersionUID = 1L; 
10.     /\*\*
11.      \* request
12.      \*/ 
13.     **private** Map <String,Object>request; 
14.     /\*\*
15.      \* response
16.      \*/ 
17.     **private** Map <String,Object>session; 
18.     /\*\*
19.      \* application
20.      \*/ 
21.     **private** Map <String,Object>application; 
22.     /\*\*
23.      \* 控制器
24.      \*/ 
25.     @SuppressWarnings("unchecked") 
26.     @Override 
27.     **public** String execute()\{ 
28.         System.out.println("通过实现RequestAware、SessionAware、ApplicationAware接口来访问request,session,application对象"); 
29.         // 赋值 
30.         request.put("requestKey", "requestValue"); 
31.         session.put("sessionKey", "sessionValue"); 
32.         application.put("applicationKey", "applicationValue"); 
33.         **return** "success"; 
34.     \} 
35.     /\*
36.      \* 实现RequestAware中的方法
37.      \*/ 
38.     @Override 
39.     **public** **void** setRequest(Map<String, Object> request) \{ 
40.         **this**.request = request; 
41.     \} 
42.     /\*
43.      \* 实现ApplicationAware中的方法
44.      \*/ 
45.     @Override 
46.     **public** **void** setApplication(Map<String, Object> application) \{ 
47.         **this**.application = application; 
48.     \} 
49.     /\*
50.      \* 实现SessionAware中的方法
51.      \*/ 
52.     @Override 
53.     **public** **void** setSession(Map<String, Object> session) \{ 
54.         **this**.session = session; 
55.     \} 
56. \}

**\[java\]**  [view plain][] [copy][view plain]

1.  /\*\* 
2.   \* 通过实现RequestAware、SessionAware、ApplicationAware接口来访问request,session,application对象 
3.   \* @author 健 
4.   \*/  
5.  **public** **class** UserAction2 **extends** ActionSupport **implements** RequestAware,SessionAware,ApplicationAware\{  
6.      /\*\* 
7.       \* 序列化 
8.       \*/  
9.      **private** **static** **final** **long** serialVersionUID = 1L;  
10.     /\*\* 
11.      \* request 
12.      \*/  
13.     **private** Map <String,Object>request;  
14.     /\*\* 
15.      \* response 
16.      \*/  
17.     **private** Map <String,Object>session;  
18.     /\*\* 
19.      \* application 
20.      \*/  
21.     **private** Map <String,Object>application;  
22.     /\*\* 
23.      \* 控制器 
24.      \*/  
25.     @SuppressWarnings("unchecked")  
26.     @Override  
27.     **public** String execute()\{  
28.         System.out.println("通过实现RequestAware、SessionAware、ApplicationAware接口来访问request,session,application对象");  
29.         // 赋值  
30.         request.put("requestKey", "requestValue");  
31.         session.put("sessionKey", "sessionValue");  
32.         application.put("applicationKey", "applicationValue");  
33.         **return** "success";  
34.     \}  
35.     /\*  
36.      \* 实现RequestAware中的方法 
37.      \*/  
38.     @Override  
39.     **public** **void** setRequest(Map<String, Object> request) \{  
40.         **this**.request = request;  
41.     \}  
42.     /\*  
43.      \* 实现ApplicationAware中的方法 
44.      \*/  
45.     @Override  
46.     **public** **void** setApplication(Map<String, Object> application) \{  
47.         **this**.application = application;  
48.     \}  
49.     /\*  
50.      \* 实现SessionAware中的方法 
51.      \*/  
52.     @Override  
53.     **public** **void** setSession(Map<String, Object> session) \{  
54.         **this**.session = session;  
55.     \}  
56. \}

方式三：

Java代码  [![复制代码][icon_copy.gif]][icon_copy.gif 1]

1.  \+/\*\*
2.  \* 通过ServletActionContext来访问request,session,application对象
3.  \* @author 健
4.  \*/ 
5.  **public** **class** UserAction3 **extends** ActionSupport\{ 
6.      /\*\*
7.       \* 序列化
8.       \*/ 
9.      **private** **static** **final** **long** serialVersionUID = 1L; 
10.     /\*\*
11.      \* request
12.      \*/ 
13.     **private** HttpServletRequest request; 
14.     /\*\*
15.      \* response
16.      \*/ 
17.     **private** HttpSession session; 
18.     /\*\*
19.      \* application
20.      \*/ 
21.     **private** ServletContext application; 
22.     /\*\*
23.      \* 控制器
24.      \*/ 
25.     @SuppressWarnings("unchecked") 
26.     @Override 
27.     **public** String execute()\{ 
28.         System.out.println("通过ServletActionContext来访问request,session,application对象"); 
29.         // 初始化 
30.         request = ServletActionContext.getRequest(); 
31.         session = request.getSession(); 
32.         application = session.getServletContext(); 
33.         // 赋值 
34.         request.setAttribute("requestKey", "requestValue"); 
35.         session.setAttribute("sessionKey", "sessionValue"); 
36.         application.setAttribute("applicationKey", "applicationValue"); 
37.         **return** "success"; 
38.     \} 
39. \}

**\[java\]**  [view plain][] [copy][view plain]

1.  \+/\*\* 
2.   \* 通过ServletActionContext来访问request,session,application对象 
3.   \* @author 健 
4.   \*/  
5.  **public** **class** UserAction3 **extends** ActionSupport\{  
6.      /\*\* 
7.       \* 序列化 
8.       \*/  
9.      **private** **static** **final** **long** serialVersionUID = 1L;  
10.     /\*\* 
11.      \* request 
12.      \*/  
13.     **private** HttpServletRequest request;  
14.     /\*\* 
15.      \* response 
16.      \*/  
17.     **private** HttpSession session;  
18.     /\*\* 
19.      \* application 
20.      \*/  
21.     **private** ServletContext application;  
22.     /\*\* 
23.      \* 控制器 
24.      \*/  
25.     @SuppressWarnings("unchecked")  
26.     @Override  
27.     **public** String execute()\{  
28.         System.out.println("通过ServletActionContext来访问request,session,application对象");  
29.         // 初始化  
30.         request = ServletActionContext.getRequest();  
31.         session = request.getSession();  
32.         application = session.getServletContext();  
33.         // 赋值  
34.         request.setAttribute("requestKey", "requestValue");  
35.         session.setAttribute("sessionKey", "sessionValue");  
36.         application.setAttribute("applicationKey", "applicationValue");  
37.         **return** "success";  
38.     \}  
39. \}

方式四：

Java代码  [![复制代码][icon_copy.gif]][icon_copy.gif 1]

1.  /\*\*
2.  \* 通过实现ServletRequestAware接口来访问request,session,application对象
3.  \* @author 健
4.  \*/ 
5.  **public** **class** UserAction4 **extends** ActionSupport **implements** ServletRequestAware\{ 
6.      /\*\*
7.       \* 序列化
8.       \*/ 
9.      **private** **static** **final** **long** serialVersionUID = 1L; 
10.     /\*\*
11.      \* request
12.      \*/ 
13.     **private** HttpServletRequest request; 
14.     /\*\*
15.      \* response
16.      \*/ 
17.     **private** HttpSession session; 
18.     /\*\*
19.      \* application
20.      \*/ 
21.     **private** ServletContext application; 
22.     /\*\*
23.      \* 控制器
24.      \*/ 
25.     @SuppressWarnings("unchecked") 
26.     @Override 
27.     **public** String execute()\{ 
28.         System.out.println("通过实现ServletRequestAware接口来访问request,session,application对象"); 
29.         // 赋值 
30.         request.setAttribute("requestKey", "requestValue"); 
31.         session.setAttribute("sessionKey", "sessionValue"); 
32.         application.setAttribute("applicationKey", "applicationValue"); 
33.         **return** "success"; 
34.     \} 
35.     /\*
36.      \* 实现ServletRequestAware接口中的方法
37.      \*/ 
38.     @Override 
39.     **public** **void** setServletRequest(HttpServletRequest request) \{ 
40.         **this**.request = request; 
41.         **this**.session = request.getSession(); 
42.         **this**.application = session.getServletContext(); 
43.     \} 
44. \}

**\[java\]**  [view plain][] [copy][view plain]

1.  /\*\* 
2.   \* 通过实现ServletRequestAware接口来访问request,session,application对象 
3.   \* @author 健 
4.   \*/  
5.  **public** **class** UserAction4 **extends** ActionSupport **implements** ServletRequestAware\{  
6.      /\*\* 
7.       \* 序列化 
8.       \*/  
9.      **private** **static** **final** **long** serialVersionUID = 1L;  
10.     /\*\* 
11.      \* request 
12.      \*/  
13.     **private** HttpServletRequest request;  
14.     /\*\* 
15.      \* response 
16.      \*/  
17.     **private** HttpSession session;  
18.     /\*\* 
19.      \* application 
20.      \*/  
21.     **private** ServletContext application;  
22.     /\*\* 
23.      \* 控制器 
24.      \*/  
25.     @SuppressWarnings("unchecked")  
26.     @Override  
27.     **public** String execute()\{  
28.         System.out.println("通过实现ServletRequestAware接口来访问request,session,application对象");  
29.         // 赋值  
30.         request.setAttribute("requestKey", "requestValue");  
31.         session.setAttribute("sessionKey", "sessionValue");  
32.         application.setAttribute("applicationKey", "applicationValue");  
33.         **return** "success";  
34.     \}  
35.     /\*  
36.      \* 实现ServletRequestAware接口中的方法 
37.      \*/  
38.     @Override  
39.     **public** **void** setServletRequest(HttpServletRequest request) \{  
40.         **this**.request = request;  
41.         **this**.session = request.getSession();  
42.         **this**.application = session.getServletContext();  
43.     \}  
44. \}

上面的action配套的struts.xml及jsp页面

struts.xml

Xhtml代码  [![复制代码][icon_copy.gif]][icon_copy.gif 1]

1.  **<****struts****>** 
2.       
3.      **<****constant** name="struts.devMode" value="true"**/>** 
4.      **<****package** name="" namespace="/login" extends="struts-default"**>** 
5.          **<****action** name="login\*" class="com.wj.struts2.action.UserAction\{1\}"**>** 
6.              **<****result** name="success"**>**/success.jsp**</****result****>** 
7.              **<****result** name="failure"**>**/failure.jsp**</****result****>** 
8.          **</****action****>** 
9.      **</****package****>** 
10. **</****struts****>**

**\[xhtml\]**  [view plain][] [copy][view plain]

1.  **<****struts****>**  
2.        
3.      **<****constant** name="struts.devMode" value="true"**/>**  
4.      **<****package** name="" namespace="/login" extends="struts-default"**>**  
5.          **<****action** name="login\*" class="com.wj.struts2.action.UserAction\{1\}"**>**  
6.              **<****result** name="success"**>**/success.jsp**</****result****>**  
7.              **<****result** name="failure"**>**/failure.jsp**</****result****>**  
8.          **</****action****>**  
9.      **</****package****>**  
10. **</****struts****>**

index.jsp

Xhtml代码  [![复制代码][icon_copy.gif]][icon_copy.gif 1]

1.  **<**%@ page language="java" import="java.util.\*" pageEncoding="UTF-8"%**>** 
2.  **<**%@taglib uri="/struts-tags" prefix="s" %**>** 
3.  **<**% 
4.      String path = request.getContextPath(); 
5.      String basePath = request.getScheme() + "://" 
6.              + request.getServerName() + ":" + request.getServerPort() 
7.              + path + "/"; 
8.  %**>** 
9.  <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"**>** 
10. **<****html****>** 
11.     **<****head****>** 
12.         **<****base** href="<%=basePath%>"**>** 
13.  
14.         **<****title****>**Struts2\_AccessWebElements**</****title****>** 
15.         **<****meta** http-equiv="pragma" content="no-cache"**>** 
16.         **<****meta** http-equiv="cache-control" content="no-cache"**>** 
17.         **<****meta** http-equiv="expires" content="0"**>** 
18.         **<****meta** http-equiv="keywords" content="keyword1,keyword2,keyword3"**>** 
19.         **<****meta** http-equiv="description" content="This is my page"**>** 
20.          
23.         **<****mce:script** language="javascript"**>**<!-- 
24.             function sub(str)\{ 
25.                 document.form1.action = str; 
26.                 document.form1.submit(); 
27.             \} 
28.          
29. // --**>****</****mce:script****>** 
30.     **</****head****>** 
31.  
32.     **<****body****>** 
33.         **<****form** name="form1"**>** 
34.             **<****div****>** 
35.                 Struts2中访问web元素的四种方式**<****br****>** 
36.                 方式一：**<****input** type="button" value="submit1" onclick="sub('<%=basePath%>login/login1')"**>****<****br****>**   
37.                 方式二：**<****input** type="button" value="submit2" onclick="sub('<%=basePath%>login/login2')"**>****<****br****>** 
38.                 方式三：**<****input** type="button" value="submit3" onclick="sub('<%=basePath%>login/login3')"**>****<****br****>** 
39.                 方式四：**<****input** type="button" value="submit4" onclick="sub('<%=basePath%>login/login4')"**>****<****br****>** 
40.             **</****div****>** 
41.         **</****form****>** 
42.     **</****body****>** 
43. **</****html****>**

**\[xhtml\]**  [view plain][] [copy][view plain]

1.  **<**%@ page language="java" import="java.util.\*" pageEncoding="UTF-8"%**>**  
2.  **<**%@taglib uri="/struts-tags" prefix="s" %**>**  
3.  **<**%  
4.      String path = request.getContextPath();  
5.      String basePath = request.getScheme() + "://"  
6.              + request.getServerName() + ":" + request.getServerPort()  
7.              + path + "/";  
8.  %**>**  
9.  <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"**>**  
10. **<****html****>**  
11.     **<****head****>**  
12.         **<****base** href="<%=basePath%>"**>**  
13.   
14.         **<****title****>**Struts2\_AccessWebElements**</****title****>**  
15.         **<****meta** http-equiv="pragma" content="no-cache"**>**  
16.         **<****meta** http-equiv="cache-control" content="no-cache"**>**  
17.         **<****meta** http-equiv="expires" content="0"**>**  
18.         **<****meta** http-equiv="keywords" content="keyword1,keyword2,keyword3"**>**  
19.         **<****meta** http-equiv="description" content="This is my page"**>**  
20.           
23.         **<****mce:script** language="javascript"**>**<!--  
24.             function sub(str)\{  
25.                 document.form1.action = str;  
26.                 document.form1.submit();  
27.             \}  
28.           
29. // --**>****</****mce:script****>**  
30.     **</****head****>**  
31.   
32.     **<****body****>**  
33.         **<****form** name="form1"**>**  
34.             **<****div****>**  
35.                 Struts2中访问web元素的四种方式**<****br****>**  
36.                 方式一：**<****input** type="button" value="submit1" onclick="sub('<%=basePath%>login/login1')"**>****<****br****>**    
37.                 方式二：**<****input** type="button" value="submit2" onclick="sub('<%=basePath%>login/login2')"**>****<****br****>**  
38.                 方式三：**<****input** type="button" value="submit3" onclick="sub('<%=basePath%>login/login3')"**>****<****br****>**  
39.                 方式四：**<****input** type="button" value="submit4" onclick="sub('<%=basePath%>login/login4')"**>****<****br****>**  
40.             **</****div****>**  
41.         **</****form****>**  
42.     **</****body****>**  
43. **</****html****>**

success.jsp

Xhtml代码  [![复制代码][icon_copy.gif]][icon_copy.gif 1]

1.  **<**%@ page language="java" import="java.util.\*" pageEncoding="UTF-8"%**>** 
2.  **<**%@taglib uri="/struts-tags" prefix="s" %**>** 
3.  **<**% 
4.      String path = request.getContextPath(); 
5.      String basePath = request.getScheme() + "://" 
6.              + request.getServerName() + ":" + request.getServerPort() 
7.              + path + "/"; 
8.  %**>** 
9.  <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"**>** 
10. **<****html****>** 
11.     **<****head****>** 
12.         **<****base** href="<%=basePath%>"**>** 
13.         **<****title****>**Struts2\_AccessWebElements**</****title****>** 
14.         **<****meta** http-equiv="pragma" content="no-cache"**>** 
15.         **<****meta** http-equiv="cache-control" content="no-cache"**>** 
16.         **<****meta** http-equiv="expires" content="0"**>** 
17.         **<****meta** http-equiv="keywords" content="keyword1,keyword2,keyword3"**>** 
18.         **<****meta** http-equiv="description" content="This is my page"**>** 
19.          
22.     **</****head****>** 
23.  
24.     **<****body****>** 
25.         requestKey---**<****s:property** value="\#request.requestKey"**/>**|**<**%=request.getAttribute("requestKey")%**>****<****br****>** 
26.         sessionKey---**<****s:property** value="\#session.sessionKey"**/>**|**<**%=session.getAttribute("sessionKey")%**>****<****br****>** 
27.         applicationKey---**<****s:property** value="\#application.applicationKey"**/>**|**<**%=application.getAttribute("applicationKey")%**>****<****br****>** 
28.         -------------------------------------------- 
29.         **<****s:debug****>****</****s:debug****>** 
30.     **</****body****>** 
31. **</****html****>**

**\[xhtml\]**  [view plain][] [copy][view plain]

1.  **<**%@ page language="java" import="java.util.\*" pageEncoding="UTF-8"%**>**  
2.  **<**%@taglib uri="/struts-tags" prefix="s" %**>**  
3.  **<**%  
4.      String path = request.getContextPath();  
5.      String basePath = request.getScheme() + "://"  
6.              + request.getServerName() + ":" + request.getServerPort()  
7.              + path + "/";  
8.  %**>**  
9.  <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"**>**  
10. **<****html****>**  
11.     **<****head****>**  
12.         **<****base** href="<%=basePath%>"**>**  
13.         **<****title****>**Struts2\_AccessWebElements**</****title****>**  
14.         **<****meta** http-equiv="pragma" content="no-cache"**>**  
15.         **<****meta** http-equiv="cache-control" content="no-cache"**>**  
16.         **<****meta** http-equiv="expires" content="0"**>**  
17.         **<****meta** http-equiv="keywords" content="keyword1,keyword2,keyword3"**>**  
18.         **<****meta** http-equiv="description" content="This is my page"**>**  
19.           
22.     **</****head****>**  
23.   
24.     **<****body****>**  
25.         requestKey---**<****s:property** value="\#request.requestKey"**/>**|**<**%=request.getAttribute("requestKey")%**>****<****br****>**  
26.         sessionKey---**<****s:property** value="\#session.sessionKey"**/>**|**<**%=session.getAttribute("sessionKey")%**>****<****br****>**  
27.         applicationKey---**<****s:property** value="\#application.applicationKey"**/>**|**<**%=application.getAttribute("applicationKey")%**>****<****br****>**  
28.         --------------------------------------------  
29.         **<****s:debug****>****</****s:debug****>**  
30.     **</****body****>**  
31. **</****html****>**

前台jsp页面获取后台值的方式

<s:property value="\#request.requestKey"/>|<%=request.getAttribute("requestKey")%>

<s:property value="\#session.sessionKey"/>|<%=session.getAttribute("sessionKey")%>

<s:property value="\#application.applicationKey"/>|<%=application.getAttribute("applicationKey")%>

[icon_copy.gif]: http://newleague.iteye.com/images/icon_copy.gif
[icon_copy.gif 1]: /images/20220810/3a84a3f259884d0aab34379774481443.png
[view plain]: http://blog.csdn.net/mr_walter/article/details/7871790#