Struts 2.0 解读笔记

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struts2 的demo 中的employee层可以清晰的暂时struts希望给开发者带来的架构

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EmployeeAction ^
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EmployeeDao ^
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Employee

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struts.xml 配置

<package name="skill" extends="default" namespace="/skill"><br><default-interceptor-ref name="crudStack"></default-interceptor-ref></package>

<action name="list" class="org.apache.struts2.showcase.action.SkillAction" method="list"><br><result>/empmanager/listSkills.jsp</result><br><interceptor-ref name="basicStack"></interceptor-ref><br></action>
<action name="edit" class="org.apache.struts2.showcase.action.SkillAction"><br><result>/empmanager/editSkill.jsp</result><br><interceptor-ref name="params"></interceptor-ref><br><interceptor-ref name="basicStack"></interceptor-ref><br></action>
<action name="save" class="org.apache.struts2.showcase.action.SkillAction" method="save"><br><result name="input">/empmanager/editSkill.jsp</result><br><result type="redirect">edit.action?skillName=${currentSkill.name}</result><br></action>
<action name="delete" class="org.apache.struts2.showcase.action.SkillAction" method="delete"><br><result name="error">/empmanager/editSkill.jsp</result><br><result type="redirect">edit.action?skillName=${currentSkill.name}</result> 这里展现了struts2具有良好的url特性，比起ww的crud!edit让人舒服多了<br></action>

<package name="employee" extends="default" namespace="/employee"><br><default-interceptor-ref name="crudStack"></default-interceptor-ref></package>

<action name="list" class="org.apache.struts2.showcase.action.EmployeeAction" method="list"><br><result>/empmanager/listEmployees.jsp</result><br><interceptor-ref name="basicStack"></interceptor-ref><br></action>
<action name="edit-*" class="org.apache.struts2.showcase.action.EmployeeAction"><br><param name="empId">{1}<br><result>/empmanager/editEmployee.jsp</result><br><interceptor-ref name="crudStack"><param name="validation.excludeMethods">execute</interceptor-ref><br></action>
<action name="save" class="org.apache.struts2.showcase.action.EmployeeAction" method="save"><br><result name="input">/empmanager/editEmployee.jsp</result><br><result type="redirect">edit-${currentEmployee.empId}.action</result><br></action>
<action name="delete" class="org.apache.struts2.showcase.action.EmployeeAction" method="delete"><br><result name="error">/empmanager/editEmployee.jsp</result><br><result type="redirect">edit-${currentEmployee.empId}.action</result><br></action>


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每一个action有自己的properties文件，非常便于管理和代码生成，
当然也有一个全局的globalMessages.properties来存放一些save,delete这些都一样的字符
employee=Employee
employee.firstName=First Name
employee.lastName=Last Name
employee.description=Description

employee.id.required=Id is required
employee.lastName.required=Last Name is required
employee.birthDate.required=Birthdate is required
employee.backtolist=Back to Employee List

每个action自己的validation
<?xml version="1.0" encoding="UTF-8"?>
ttp://www.opensymphony.com/xwork/xwork-validator-1.0.dtd">http://www.opensymphony.com/xwork/xwork-validator-1.0.dtd">
<validators><br><!-- Field-Validator Syntax --><br><field name="currentEmployee.empId"><br><field-validator type="required"><br><message key="employee.id.required"></message><br></field-validator><br></field><br><field name="currentEmployee.lastName"><br><field-validator type="requiredstring"><br><param name="trim">true<br><message key="employee.lastName.required"></message><br></field-validator><br></field><br><field name="currentEmployee.birthDate"><br><field-validator type="required"><br><message key="employee.birthDate.required"></message><br></field-validator><br></field><br></validators>

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DAO是spring的bean,spring默认作为struts2的业务组件容器
在struts.properties中struts.objectFactory = spring

由于这里是autowire，Autowiring means to look for objects defined in Spring with the same name as your object property
所以action中所有用到IoC的地方，都会自动注入（因为action本质也是bean，下面会讲到）

<beans default-autowire="byName"> wire有四种方法：name， type， auto， constructor</beans>

<bean id="skillDao" class="org.apache.struts2.showcase.dao.SkillDao"></bean>
<bean id="employeeDao" class="org.apache.struts2.showcase.dao.EmployeeDao"></bean>

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struts2中的每一个action,也就是struts.xml里面声明的action,最终都将作为spring中的一个bean完成请求。
如果你不做额外的设定，struts2会自动生成这个bean。
如果你有特殊的需要，还可以在applicationContext.xml自己声明这个bean
你必须根据需要来决定是否再次声明
struts.xml
br /> "-//Apache Software Foundation//DTD Struts Configuration 2.0//EN"
"http://struts.apache.org/dtds/struts-2.0.dtd">
<struts><br><include file="struts-default.xml"></include></struts>

<package name="default" extends="struts-default"><br><action name="foo" class="com.acme.Foo"> 这个foo，在applicationConext.xml中没有声明，struts会自动生成一个bean<br><result>foo.ftl</result><br></action><br></package>

<package name="secure" namespace="/secure" extends="default"><br><action name="bar" class="bar"> 这个foo，在applicationConext.xml中声明了，struts会使用下面配置<br><result>bar.ftl</result><br></action><br></package>

applicationConext.xml
<?xml version="1.0" encoding="UTF-8"?>
ttp://www.springframework.org/dtd/spring-beans.dtd">http://www.springframework.org/dtd/spring-beans.dtd">
<beans default-autowire="autodetect"><br><bean id="bar" class="com.my.BarClass" singleton="false"></bean><br> ...<br></beans>

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无缝集成ajax
只要声明了theme="ajax"，该标签控件的操作就被转换成ajax，请求发送到AjaxRemoteForm
Configured Editor configuration:

<submit value="Submit"></submit>

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集成了多种模板
jsp,velocity,freemaker

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struts2 继承了ww2的优良传统，并且摈弃了ww2的一些缺陷，也可以看成是对ww2的一次重购。
无疑是目前最主流，最强大的MVC框架了。

它实现了和spring的完美结合

集成了ajax（dojo+dwr）

其插件支持jasperreports，jfreechart