在Struts2中,采用Validation Interceptor来完成校验支持,在struts-default.xml中,先调用conversionError interceptor进行type conversion操作,然后调用params 、prepare、validation interceptor完成对字段校验,interceptor的执行顺序是
- 型别转换 (type conversion)
- 获取参数信心(params )
- 为验证等作准备(prepare)
- 参数验证 (validation)
如果在进行type conversion时候发生错误,struts2对同样的字段就不会进行验证,会抛出异常,例如页面一输入字段希望进行是否为整数验证,由于页面输入值缺省都为String类型,因此会在后台抛出类似的错误:
ERROR (com.opensymphony.xwork2.interceptor.ParametersInterceptor:204) – ParametersInterceptor – [setParameters]: Unexpected Exception caught setting ‘integerTest’ on ‘class com.mobilesoft.esales.webapp.action.MyValidationAction: Error setting expression ‘integerTest’ with value ‘[Ljava.lang.String;@11e170c’
而在验证页面,会抛出如下的错误信息:
Invalid field value for field “integerTest”
怎么把”Invalid field value for …” 这样的信息转化成我们指定的信息,方法有几个:
1、自定义转换类
将页面非String 类型的property转换成指定的类型,这样进行validation验证
参看http://struts.apache.org/2.0.11.1/docs/type-conversion.html
对于页面输入有意义的validator实际上只有required、date、int几个有意义,其它的意义都不大;同时由于要做单独的类型转换类,比较麻烦,不采用此种方式
2、采用struts2的i18n支持
又有几种方法
2.1、在资源文件中设定全局的xwork.default.invalid.fieldvalue 属性
xwork.default.invalid.fieldvalue=数据格式不正确
2.2、在资源文件中设定invalid.fieldvalue.字段名称属性
invalid.fieldvalue.integerTest=数据格式不正确
2.3、定义针对每一个Action的properties文件
例如在MyValidationAction.properties(与MyValidationAction放在同一目录中,而不是在classes下)中定义
invalid.fieldvalue.integerTest=数据格式不正确
注意:
- 目前在架构中,资源文件命名为ApplicationResources.properties,ApplicationResources_zh.properties,在web.xml中定义的:
<context-param>
<param-name>javax.servlet.jsp.jstl.fmt.localizationContext</param-name>
<param-value>ApplicationResources</param-value>
</context-param>
- struts2缺省提供了一些type conversion 类,能够完成一些基本的转换操作:
String
boolean / Boolean
char / Character
int / Integer, float / Float, long / Long, double / Double
dates – uses the SHORT format for the Locale associated with the current request
arrays – assuming the individual strings can be coverted to the individual items
collections – if not object type can be determined, it is assumed to be a String and a new ArrayList is created
- 要完成客户端校验,注意在<s:form >上添加validate=”true”
<s:form action =”myValidationAction” validate=”true” >
- 注意对资源文件进行native2ascii操作,或者用eclipse的PropEditor插件(http://propedit.sourceforge.jp/eclipse/updates)直接编辑
3、例子
3.1、validationInput.jsp
<%@ taglib prefix=”s” uri=”/struts-tags” %>
<%@ page language=”java” errorPage=”/error.jsp” pageEncoding=”GBK” contentType=”text/html;charset=GBK” %>
<html>
<head>
<title> Validation测试 </title>
<s:head />
</head>
<body>
<s:form action =”myValidationAction” validate=”true” >
<s:textfield name =”strTest” label =”String类型测试” />
<s:textfield name =”integerTest” label =”Integer类型测试” />
<s:textfield name =”emailTest” label =”email类型测试” />
<s:submit />
</s:form>
</body>
</html>
3.2、validationOutput.jsp
<%@ taglib prefix=”s” uri=”/struts-tags” %>
<%@ page language=”java” errorPage=”/error.jsp” pageEncoding=”GBK” contentType=”text/html;charset=GBK” %>
<html>
<head>
<title> Hello World </title>
</head>
<body>
String类型测试: <s:property value =”strTest” /> <br/>
Integer类型测试: <s:property value =”integerTest” /> <br/>
email类型测试: <s:property value =”emailTest” /> <br/>
</body>
</html>
3.3、MyValidationAction-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=”strTest”>
<field-validator type=”requiredstring”>
<message>字段不能为空</message>
</field-validator>
</field>
<field name=”integerTest”>
<field-validator type=”conversion”>
<message>conversion</message>
</field-validator>
<field-validator type=”required”>
<message>字段不能为空</message>
</field-validator>
<field-validator type=”int”>
<param name=”min”>6</param>
<param name=”max”>10</param>
<message>值必须在 [ ${min}, ${max}], 当前的值是: ${integerTest}.</message>
</field-validator>
</field>
<field name=”emailTest”>
<field-validator type=”required”>
<message>字段不能为空</message>
</field-validator>
<field-validator type=”email”>
<message>字段必须为邮件地址</message>
</field-validator>
</field>
</validators>
3.4、MyValidationAction.java
package com.mobilesoft.esales.webapp.action;
public class MyValidationAction extends BaseAction {
private Stri
ng strTest;
private Integer integerTest;
private String emailTest;
public String execute(){
return SUCCESS;
}
public String getStrTest() {
return strTest;
}
public void setStrTest(String strTest) {
this.strTest = strTest;
}
public Integer getIntegerTest() {
return integerTest;
}
public void setIntegerTest(Integer integerTest) {
this.integerTest = integerTest;
}
public String getEmailTest() {
return emailTest;
}
public void setEmailTest(String emailTest) {
this.emailTest = emailTest;
}
}
3.5、struts.xml
<action name=”myValidationAction” method=”execute” class=”com.mobilesoft.esales.webapp.action.MyValidationAction”>
<result name=”success”>validationOutput.jsp</result>
<result name=”input”>validationInput.jsp</result>
</action>
4、参考文档
http://struts.apache.org/2.x/docs/validation.html
http://struts.apache.org/2.0.11.1/docs/type-conversion.html
http://struts.apache.org/2.x/docs/localizing-output.html