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今天研究了一下JpetStore源代碼 ,發(fā)現(xiàn)它的開發(fā)strust模式和我們以往開發(fā)的模式完全不同,所有的strust類都繼承org.apache.struts.beanaction.BaseBean

仔細(xì)研究BeanAction類，發(fā)現(xiàn)它其實(shí)是一個(gè)通用類，利用反射原理，根據(jù)URL來決定調(diào)用formbean的哪個(gè)方法！

一個(gè)簡單的例子

package ?strutstest.action;
// 繼承BaseBean
import ?org.apache.struts.beanaction.BaseBean;

public ? class ?TestBean? extends ?BaseBean? {
????
???? public ? static ? final ?String?SUCCESS? = ? " success " ;
???? public ? static ? final ?String?FAILURE? = ? " failure " ;
???? public ?TestBean()? {
????}
???? private ?String?id;
???? private ? int ?age;
???? private ?String?name;
???? private ?String?address;
???? // getter?setter
// 定義幾個(gè)業(yè)務(wù)方法
???? public ?String?saveUser()
?????? {
??????????System.out.print( " 添加用戶.. " );
?????????? // 這里返回一個(gè)字符串,將自動(dòng)導(dǎo)向成功頁
?????????? // 對應(yīng)的是 forward 的名稱
?????????? return ?SUCCESS;
??????}
?????? public ?String?updateUser()
?????? {
??????????System.out.print( " update?user.. " );
?????????
?????????? return ?SUCCESS;
??????}
?????? public ?String?getUser()
?????? {
?????????? if (id == null )
?????????? {
?????????????System.out.print( " 沒有此用戶 " );
????????????? // 導(dǎo)向失敗
?????????????retutn?FAILURE;?
???????????}
??????????
??????????System.out.print( " 用戶id= " + id);
?????????? return ?SUCCESS;
??????}

<struts-config>
??<form-beans>
????<form-bean?name="testBean"?type="strutstest.action.TestBean"?/>
??</form-beans>
??<action-mappings>
????<action?name="testBean"?path="/test/saveUser"?type="org.apache.struts.beanaction.BeanAction">
??????<forward?name="success"?path="/success.html"?/>
????</action>
????<action?name="testBean"?parameter="*"?path="/test/index"?type="org.apache.struts.beanaction.BeanAction"?validate="false">
??????<forward?name="success"?path="/user.jsp"?/>
????</action>
????<action?name="testBean"?path="/test/updateUser"?type="org.apache.struts.beanaction.BeanAction">
??????<forward?name="success"?path="/success.html"?/>
????</action>
????<action??name="testBean"?path="/test/getUser"?type="org.apache.struts.beanaction.BeanAction"?>
?????????<forward?name="success"?path="/success.html"?/>
????</action>
??</action-mappings>

說明|:

Struts-config.xml的配置里有3種映射方式，來告訴BeanAction把控制轉(zhuǎn)到哪個(gè)form bean對象的哪個(gè)方法來處理。


<action name="testBean" path="/test/saveUser" type="org.apache.struts.beanaction.BeanAction">
????? <forward name="success" path="/success.html" />
??? </action>


此種方式表示，控制將被轉(zhuǎn)發(fā)到"testBean"這個(gè)form bean對象 的"savaUser"方法（行為）來處理。方法名取"path"參數(shù)的以"/"分隔的最后一部分。
parameter="*"

此種方式表示，form bean上沒有任何方法被調(diào)用。如果存在"name"屬性，則struts把表單參數(shù)等數(shù)據(jù)填充到form bean對象后，把控制轉(zhuǎn)發(fā)到"success"。否則，如果name為空，則直接轉(zhuǎn)發(fā)控制到"success"。這就相當(dāng)于struts內(nèi)置的org.apache.struts.actions.ForwardAction的功能

前臺(tái)調(diào)用

<html:link?page="/test/saveUser.do">
saveUser
</html:link>
<html:link?page="/test/getUser.do?id=22">
getUser
</html:link>
<html:link?page="/test/updateUser.do">
UpdateUser
</html:link>
</body>
</html:html>