Sealyu

<bean id="userValidator" class="org.springmodules.validation.valang.ValangValidator">

            <property name="valang">

            <value>

            <![CDATA[

            { name  : ? is not null and ? has text and length(?)<= 50 

            : 'Name is empty or too long.'}

            { age : ? between 0 and 60 : 'Age should between 0 and 60.'}

            |-------10--------20--------30--------40--------50--------60--------70--------80--------9|

            |-------- XML error:  The previous line is longer than the max of 90 characters ---------|

            { birthday : ? is null or ? >[20000101]

            : 'Birthday should be after 2000-01-01.'}

            { address : ? is not null : 'Address is empty.'}

            { address.state : address is null or ( ? is not null and

            ? has text and length(?)<=50 )

            : 'state is empty or too long.'}

            { address.town : address is null or ( ? is not null and  

            ? has text and length(?)<=50 )

            : 'town is empty or too long.'}

            { address.street : address is null or ( ? is not null and

            ? has text and length(?)<=50 )

            : 'street is empty or too long.'}	

            ]]>

            </value>

            </property>

            <property name="dateParsers">

            <map>

            <entry key="^""d{8}$" value="yyyyMMdd" />

            </map>

            </property>

            </bean>

            

<bean id="addressValidator" class="org.springmodules.validation.valang.ValangValidator">

            <property name="valang">

            <value>

            <![CDATA[

            { state : ? is not null and  ? has text and length(?)<=50

            : 'state is empty or too long.'}

            { town : ? is not null and  ? has text and length(?)<=50

            : 'town is empty or too long.'}

            { street : ? is not null and  ? has text and length(?)<=50

            : 'street is empty or too long.'}

            ]]>			

            </value>

            </property>

            </bean>

            

public class UserValidator extends ValangValidator {

            private Validator addressValidator;

            

            public void setAddressValidator(Validator addressValidator) {

            this.addressValidator = addressValidator;

            }

            

            public void validate(Object target, Errors errors){

            super.validate( target, errors);

            Address address= ((User)target).getAddress();

            // address 为 null 时，不进行进一步的验证。

            if( null!= address){

            //注意与 popNestedPath 成对使用

            errors.pushNestedPath("address");

            //验证 address

            addressValidator.validate( address, errors);

            errors.popNestedPath();

            }

            }

            }

            

<bean id="userValidator" class="包名.UserValidator">

            <property name="addressValidator" ref="addressValidator"/>

            <property name="valang">

            <value>

            <![CDATA[

            { name : ? is not null and ? has text and length(?)<= 50

            : 'Name is empty or too long.'}

            { age : ? between 0 and 60 : 'Age should between 0 and 60.'}

            { birthday : ? is null or ? >[20000101] : 'Birthday should be after 2000-01-01.'}

            |-------10--------20--------30--------40--------50--------60--------70--------80--------9|

            |-------- XML error:  The previous line is longer than the max of 90 characters ---------|

            { address : ? is not null : 'Address is empty.'}

            ]]>			

            </value>

            </property>

            <property name="dateParsers">

            <map>

            <entry key="^""d{8}$" value="yyyyMMdd" />

            </map>

            </property>

            </bean>

            

public class UserValidatorTest extends AbstractDependencyInjectionSpringContextTests {

            private Validator userValidator;

            

            public UserValidatorTest(){

            super();

            //缺省是AUTOWIRE_BY_TYPE，当Bean文件有2个以上的同类型

            //Bean定义时就应该采用AUTOWIRE_BY_NAME方式。

            setAutowireMode(AUTOWIRE_BY_NAME);

            }

            

            protected String[] getConfigLocations() {

            //指明配置文件的位置

            return new String[]{"file:文件路径/valang.xml"};

            }

            //基类调用该方法完成依赖注入（DI）

            public void setUserValidator(Validator userValidator) {

            this.userValidator = userValidator;

            }

            

            public void testEmptyObject(){

            User user= new User();

            BindException errors= new BindException(user, "target");

            userValidator.validate( user, errors);

            assertTrue( errors.getAllErrors().size()== 2);

            ObjectError error1= (ObjectError)(errors.getAllErrors().get(0));

            assertEquals(error1.getDefaultMessage(), "Name is empty or too long.");

            ObjectError error2= (ObjectError)(errors.getAllErrors().get(1));

            assertEquals(error2.getDefaultMessage(), "Address is empty.");

            }

            ……

            }

            

<bean id="userController" class="……">

            ……

            <property name="validator" ref="userValidator"/>

            </bean>

            

{ <key> : <predicate_expression> : <message> [: <error_code> [: <args> ]] }

<expression> ::= <expression> ( ( "AND" | "OR" ) <expression> )+ | <predicate>

public class AnotherLengthFunction extends AbstractFunction {

            

            public AnotherLengthFunction(Function[] functions, int line, int column) {

            super(functions, line, column);

            //AnotherLengthFunction只支持一个参数

            definedExactNumberOfArguments(1);

            }

            

            protected Object doGetResult(Object target) throws Exception {

            //返回参数1的toString的值。如果有多个参数，那么：

            //参数2：getArguments()[1].getResult(target).toString();以此类推。

            //另外getArguments()的个数就是实际传入的参数个数。

            String value= getArguments()[0].getResult(target).toString();

            return new Integer(value.length());

            }

            

            }

            

<property name="customFunctions">

            <map>

            <!-- 前者是函数使用的名字，后者对应函数实现的class。

            使用例子：anotherLength(?)<50

            -->

            <entry key="anotherLength" value="AnotherLengthFunction"/>

            </map>

            </property>

            

public class UserController extends SimpleFormController {

            

            protected Object formBackingObject(HttpServletRequest request){

            User user= new User();

            user.setAddress( new Address());

            return user;

            }

            

            protected ModelAndView onSubmit(Object command) throws Exception{

            User user=(User)command;

            ModelAndView mav= new ModelAndView(getSuccessView());

            //取出user的属性，放到mav中。

            mav.addObject("isSubmit", "true");//提交处理的标志。

            return mav;

            }

            

            protected void initBinder(HttpServletRequest request,

            ServletRequestDataBinder binder)

            throws Exception{

            SimpleDateFormat format= new SimpleDateFormat("yyyy-MM-dd");

            binder.registerCustomEditor(Date.class, "birthday"

            , new CustomDateEditor(format, true));

            }

            }

            

<%@ page contentType="text/html" %>

            <%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>

            <%@ taglib prefix="form" uri="http://www.springframework.org/tags/form" %>

            <!-- 包含valang标签库 -->

            <%@ taglib prefix="valang" uri="http://www.springmodules.org/tags/valang" %>

            

            <html>

            <head>

            <title>User Detail</title>

            <!-- 请将codebase包含在<head>中，确保在页面显示时，

            所需要的环境已经产生 -->

            <valang:codebase includeScriptTags="true" fieldErrorsIdSuffix="_error" 

            globalErrorsId="global_error"/>

            </head>

            

            <body>

            <c:if test="${not empty param.isSubmit}">

            <!-- 显示提交之后的User各属性值 -->

            </c:if>

            <c:if test="${empty param.isSubmit}">

            <form:form commandName="user" method="post">

            <!-- validate需要包含在<form>中，commandName

            是UserController的CommandName -->

            <valang:validate commandName="user"/>

            <div id="global_error">

            </div>

            <table>

            <tr>

            <td>name:</td>

            <td>

            <form:input path="name" />

            <!-- 注意id的命名。在_error之前的属性名实际是

            在valang验证规则中出现的属性表达式的名字。否则，将出错。

            如：以上的userValidator的例子中，如果将address相关的属性

            合并到一个中：

            { address: ? is not null 

            and address.state is not null and length(address.state)<= 50

            and address.town is not null and length(address.town)<= 50

            and address.street is not null and length(address.street)<= 50

            : 'Invalida address.'}

            那么，下面的 address 相关的属性对应的 <span> 的 id 就应该是：

            address_error，且只有一个。因为多个时，会引起 javascript 的错误。

            -->

            <span id="name_error"><form:errors path="name"/></span>

            </td>

            </tr>

            <tr>

            <td>age:</td>

            <td>

            <form:input path="age" />

            <span id="age_error"><form:errors path="age" /></span>

            </td>

            </tr>

            <tr>

            <td>birthday:</td>

            <td>

            <form:input path="birthday" />

            <span id="birthday_error"><form:errors path="birthday" /></span>

            </td>

            </tr>

            <tr>

            <td>state:</td>

            <td>

            <form:input path="address.state" />

            <span id="address.state_error"><form:errors path="address.state" /></span>

            </td>

            </tr>

            <tr>

            <td>town:</td>

            <td>

            <form:input path="address.town" />

            <span id="address.town_error"><form:errors path="address.town" /></span>

            </td>

            </tr>

            <tr>

            <td>street:</td>

            <td>

            <form:input path="address.street" />

            <span id="address.street_error"><form:errors path="address.street" /></span>

            |-------10--------20--------30--------40--------50--------60--------70--------80--------9|

            |-------- XML error:  The previous line is longer than the max of 90 characters ---------|

            </td>

            </tr>

            <tr>

            <td colspan="2">

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

            </td>

            </tr>

            </table>

            </form:form>

            </c:if>

            </body>

            </html>

            

<bean id="handlerMapping" 

            class="org.springframework.web.servlet.handler.SimpleUrlHandlerMapping">

            <property name="interceptors">

            <list>

            <ref bean="valangInterceptor"/>

            </list>

            </property>

            <property name="urlMap">

            <map>

            <entry key="/userDetail.htm"><ref bean="userController"/></entry>

            </map>

            </property>

            </bean>

            

            <bean id="userController" name="/userDetail.htm" class="example.UserController">

            <property name="formView" value="userDetail"/>

            <property name="successView" value="redirect:/userDetail.htm"/>

            <property name="validator" ref="userValidator"/>

            <property name="commandName" value="user"/>

            <property name="commandClass" value="example.User"/>

            </bean>

            

            <bean id="valangInterceptor"

            class="org.springmodules.validation.valang.javascript.taglib.ValangRulesExportInterceptor"/>

            |-------10--------20--------30--------40--------50--------60--------70--------80--------9|

            |-------- XML error:  The previous line is longer than the max of 90 characters ---------|

            

            <bean id="viewResolver"

            class="org.springframework.web.servlet.view.InternalResourceViewResolver">

            <property name="prefix" value="/WEB-INF/jsp/"/>

            <property name="suffix" value=".jsp"/>

            <property name="viewClass" value="org.springframework.web.servlet.view.JstlView"/>

            </bean>

            

胡 键，西安交通大学硕士，2000 年毕业后一直从事软件开发。2002 年开始使用 Java，在平时的项目开发中经常采用 OpenSource 的工具，如 Ant、Maven、Hibernate、Struts 等，目前正在研究信息集成方面的规范和技术。可以通过jianhgreat@hotmail.com与他取得联系，或访问个人blog：http://blog.donews.com/foxgem/。