(4)表单处理Action:PriceIncreaseFormAction
package web; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import bus.PriceIncrease; import bus.ProductManager; import com.opensymphony.xwork.ActionSupport; public class PriceIncreaseFormAction extends ActionSupport { /** Logger for this class and subclasses */ protected final Log logger = LogFactory.getLog(getClass()); private ProductManager prodMan; private PriceIncrease priceIncrease; public String execute() throws Exception { int increase = getPriceIncrease().getPercentage(); logger.info("Increasing prices by " + increase + "%."); prodMan.increasePrice(increase); return SUCCESS; } public ProductManager getProdMan() { return prodMan; } public void setProdMan(ProductManager prodMan) { this.prodMan = prodMan; } public PriceIncrease getPriceIncrease() { return priceIncrease; } public void setPriceIncrease(PriceIncrease priceIncrease) { this.priceIncrease = priceIncrease; } }
<action name="priceIncrease" class="web.PriceIncreaseFormAction"> <external-ref name="prodMan">prodMan</external-ref> <result name="input" type="velocity"> <param name="location">/WEB-INF/template/priceincrease.vm</param> </result> <!-- <result name="input" type="dispatcher"> <param name="location">/WEB-INF/jsp/priceincrease.jsp</param> </result> --> <result name="success" type="chain"> <param name="actionName">springapp</param> </result> <interceptor-ref name="externalValidationWorkflowStack" /> </action>
<interceptors> <interceptor name="reference-resolver" class="com.opensymphony.xwork.interceptor.ExternalReferencesInterceptor"/> <interceptor-stack name="externalStack"> <interceptor-ref name="reference-resolver"/> <interceptor-ref name="defaultStack"/> </interceptor-stack> <interceptor-stack name="externalValidationWorkflowStack"> <interceptor-ref name="reference-resolver"/> <interceptor-ref name="validationWorkflowStack" /> </interceptor-stack> </interceptors>
(5)数据有效性验证
l WebWork2基于XWork,采用XWork的数据有效性验证机制
l XWork的验证框架允许在执行Action之前,应用输入验证规则到Action
l 注册验证器:ww2/WEB-INF/classes/validators.xml
<validators> <validator name="required" class="com.opensymphony.xwork.validator.validators.RequiredFieldValidator"/> <validator name="requiredstring" class="com.opensymphony.webwork.validators.JavaScriptRequiredStringValidator"/> <validator name="int" class="com.opensymphony.webwork.validators.JavaScriptIntRangeFieldValidator"/> <validator name="date" class="com.opensymphony.webwork.validators.JavaScriptDateRangeFieldValidator"/> <validator name="expression" class="com.opensymphony.xwork.validator.validators.ExpressionValidator"/> <validator name="fieldexpression" class="com.opensymphony.xwork.validator.validators.FieldExpressionValidator"/> <validator name="email" class="com.opensymphony.webwork.validators.JavaScriptEmailValidator"/> <validator name="url" class="com.opensymphony.webwork.validators.JavaScriptURLValidator"/> <validator name="visitor" class="com.opensymphony.webwork.validators.JavaScriptVisitorFieldValidator"/> <validator name="conversion" class="com.opensymphony.xwork.validator.validators.ConversionErrorFieldValidator"/> <validator name="stringlength" class="com.opensymphony.xwork.validator.validators.StringLengthFieldValidator"/> </validators>
Ø 上面是XWork和WebWork2提供的一些常用验证器,可以直接使用
Ø <validator>的name属性指定验证器的引用名,在验证规则文件中使用;class属性指定验证器类的全路径
Ø 如果上面的验证器都不适合,可以扩展XWork的验证框架,自定义验证器使用,同样也在validators.xml中注册
l 激活验证:
Ø 对于需要数据有效性验证的Action,都需要在配置中添加对ValidationInterceptor的引用,
Ø 缺省的validationWorkflowStack已经包含了ValidationInterceptor的引用,通常更多的是添加validationWorkflowStack引用(如前面的Action配置所述)
l 指定验证规则(与Action类同目录):PriceIncreaseFormAction-validation.xml
<!DOCTYPE validators PUBLIC "-//OpenSymphony Group//XWork Validator 1.0//EN" "http://www.opensymphony.com/xwork/xwork-validator-1.0.dtd"> <validators> <field name="priceIncrease.percentage"> <field-validator type="required" short-circuit="true"> <message key="error.not-specified">Value required.</message> </field-validator> <field-validator type="fieldexpression" short-circuit="true"> <param name="expression">priceIncrease.percentage > 0</param> <message key="error.too-low">Value too low.</message> </field-validator> <field-validator type="int" short-circuit="true"> <param name="max">50</param> <message key="error.too-high">Value too high.</message> </field-validator> </field> </validators>
l 数据验证规则定义在xml文件中,文件名是actionName-validation.xml,其中actionName是对应的Action类名或者是其父类名,命名规则同资源束类似
l <field>定义要验证的表单域;name属性指定表单域名字
l <field-validator>指定要进行的验证;type属性指定验证器的引用 ,与validators.xml中指定的验证器引用一致,以便使用对应的验证器进行验证;short-circuit属性可选,表示如果验证失败,是否继续下面的验证
l 同一个表单域可以定义多个验证器进行验证,不同的验证器有不同的参数,如“fieldexpression”验证器有expression参数,表示要验证的表达式,而“int”验证器有max参数,表示最大数值
l <field-validator>至少要有一个<message>元素,提供验证失败的提示信息;<message>的key属性可选,用来指定提示信息为资源束中的消息,如果没有找到,使用<message>体内容提供的缺省消息
error.not-specified=Percentage not specified!!! error.too-low=You have to specify a percentage higher than ${expression}%! error.too-high=Don't be greedy - you can't raise prices by more than ${max}%!
l 在资源束中的消息可以使用${paramname}的形式使用验证器的参数,但是没法使用其它参数,这一点没有Spring MVC Framework灵活
l 另外,由于WebWork2是先设置属性值,后进行验证,而对于int型属性,如果为null,又自动转换为0,因此对于第一个验证没有太大意义(有什么更好的方法?要么自定义验证器) 
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