步骤一、创建如下validate.jsp页面：
<%@ page contentType="text/html; charset=UTF-8" %>
<%@ taglib prefix="s" uri="/struts-tags" %>

<h3>All Field Errors Will Appear Here</h3>
<s:fielderror />
<hr/>

<h3>Field Error due to 'Required String Validator Field' Will Appear Here</h3>
<s:fielderror>
    <s:param value="%{'requiredStringValidatorField'}" />
</s:fielderror>
<hr/>

<h3>Field Error due to 'String Length Validator Field' Will Appear Here</h3>
<s:fielderror>
    <s:param>stringLengthValidatorField</s:param>
</s:fielderror>
<hr/>
   
<s:form action="validate.action" namespace="/validation" method="POST" theme="xhtml">
    <s:textfield label="Required Validator Field" name="requiredValidatorField" />
    <s:textfield label="Required String Validator Field" name="requiredStringValidatorField" />
    <s:textfield label="Integer Validator Field" name="integerValidatorField" />
    <s:textfield label="Date Validator Field" name="dateValidatorField" />
    <s:textfield label="Email Validator Field" name="emailValidatorField" />
    <s:textfield label="URL Validator Field" name="urlValidatorField" />
    <s:textfield label="String Length Validator Field" name="stringLengthValidatorField" />
    <s:textfield label="Regex Validator Field" name="regexValidatorField"/>
    <s:textfield label="Field Expression Validator Field" name="fieldExpressionValidatorField" />
    <s:submit label="Submit" />
</s:form>

步骤二、建立如下的Action类：

package web.actions;

import java.util.Date;

import com.opensymphony.xwork2.ActionSupport;

public class FieldValidatorsExampleAction extends ActionSupport {

    private static final long serialVersionUID = -4829381083003175423L;

    private String requiredValidatorField = null;
    private String requiredStringValidatorField = null;
    private Integer integerValidatorField = null;
    private Date dateValidatorField = null;
    private String emailValidatorField = null;
    private String urlValidatorField = null;
    private String stringLengthValidatorField = null;
    private String regexValidatorField = null;
    private String fieldExpressionValidatorField = null;

    public Date getDateValidatorField() {
        return dateValidatorField;
    }
    public void setDateValidatorField(Date dateValidatorField) {
        this.dateValidatorField = dateValidatorField;
    }
    public String getEmailValidatorField() {
        return emailValidatorField;
    }
    public void setEmailValidatorField(String emailValidatorField) {
        this.emailValidatorField = emailValidatorField;
    }
    public Integer getIntegerValidatorField() {
        return integerValidatorField;
    }
    public void setIntegerValidatorField(Integer integerValidatorField) {
        this.integerValidatorField = integerValidatorField;
    }
    public String getRegexValidatorField() {
        return regexValidatorField;
    }
    public void setRegexValidatorField(String regexValidatorField) {
        this.regexValidatorField = regexValidatorField;
    }
    public String getRequiredStringValidatorField() {
        return requiredStringValidatorField;
    }
    public void setRequiredStringValidatorField(String requiredStringValidatorField) {
        this.requiredStringValidatorField = requiredStringValidatorField;
    }
    public String getRequiredValidatorField() {
        return requiredValidatorField;
    }
    public void setRequiredValidatorField(String requiredValidatorField) {
        this.requiredValidatorField = requiredValidatorField;
    }
    public String getStringLengthValidatorField() {
        return stringLengthValidatorField;
    }
    public void setStringLengthValidatorField(String stringLengthValidatorField) {
        this.stringLengthValidatorField = stringLengthValidatorField;
    }
    public String getFieldExpressionValidatorField() {
        return fieldExpressionValidatorField;
    }
    public void setFieldExpressionValidatorField(
            String fieldExpressionValidatorField) {
        this.fieldExpressionValidatorField = fieldExpressionValidatorField;
    }

    public String getUrlValidatorField() {
        return urlValidatorField;
    }

    public void setUrlValidatorField(String urlValidatorField) {
        this.urlValidatorField = urlValidatorField;
    }
}


步骤三、建立FieldValidatorsExampleAction-validation.xml文件，并与FieldValidatorsExampleAction类置于同一个文件夹下：

<!DOCTYPE validators PUBLIC
        "-//OpenSymphony Group//XWork Validator 1.0.2//EN"
        "http://www.opensymphony.com/xwork/xwork-validator-1.0.2.dtd">

<validators>
 <field name="requiredValidatorField">
  <field-validator type="required">
   <message><![CDATA[ required ]]></message>
  </field-validator>
 </field>
 <field name="requiredStringValidatorField">
  <field-validator type="requiredstring">
   <param name="trim">true</param>
   <message><![CDATA[ required and must be string ]]></message>
  </field-validator>
 </field>
 <field name="integerValidatorField">
  <field-validator type="int">
   <param name="min">1</param>
   <param name="max">10</param>
   <message><![CDATA[ must be integer min 1 max 10 if supplied ]]></message>
  </field-validator>
 </field>
 <field name="dateValidatorField">
  <field-validator type="date">
   <param name="min">01/01/1990</param>
   <param name="max">01/01/2000</param>
   <message><![CDATA[ must be a min 01-01-1990 max 01-01-2000 if supplied ]]></message>
  </field-validator>
 </field>
 <field name="emailValidatorField">
  <field-validator type="email">
   <message><![CDATA[ must be a valid email if supplied ]]></message>
  </field-validator>
 </field>
 <field name="urlValidatorField">
  <field-validator type="url">
   <message><![CDATA[ must be a valid url if supplied ]]></message>
  </field-validator>
 </field>
 <field name="stringLengthValidatorField">
  <field-validator type="stringlength">
   <param name="maxLength">4</param>
   <param name="minLength">2</param>
   <param name="trim">true</param>
   <message><![CDATA[ must be a String of a specific greater than 1 less than 5 if specified ]]></message>
  </field-validator>
 </field>
 <field name="regexValidatorField">
  <field-validator type="regex">
   <param name="expression">.*\.txt</param>
   <message><![CDATA[ regexValidatorField must match a regexp (.*\.txt) if specified ]]></message>
  </field-validator>
 </field>
 <field name="fieldExpressionValidatorField">
  <field-validator type="fieldexpression">
   <param name="expression">(fieldExpressionValidatorField == requiredValidatorField)</param>
   <message><![CDATA[ must be the same as the Required Validator Field if specified ]]></message>
  </field-validator>
 </field>
</validators>

步骤四、配置struts.xml，加入新的action映射：
  <action name="validate" class="web.actions.FieldValidatorsExampleAction">
   <result name="success">/showinfo.jsp</result>
   <result name="input">/validate.jsp</result>
  </action>