基于strut2的一个登录验证框架示例

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE validators PUBLIC
        "-//Apache Struts//XWork Validator 1.0.2//EN"
        "http://struts.apache.org/dtds/xwork-validator-1.0.2.dtd">
 <validators>
  <field name="name">
  <field-validator type="requiredstring">
   <param name="trim">true</param>
   <message>用户名不能为空!</message>
  </field-validator>
  <field-validator type="stringlength">
   <param name="minLength">5</param>
   <param name="maxLength">8</param>
   <message>用户名长度必须超过4个字符同时不得大于8个字符</message>
  </field-validator>
  </field>
  <field name="password">
   <field-validator type="requiredstring">
    <param name="trim">true</param>
    <message>密码不能为空!</message>   
   </field-validator>
   <field-validator type="stringlength">
    <param name="minLength">6</param>
    <message>密码不少于6个字符</message>
   </field-validator>
  </field>
 </validators>