struts 2.18客户端证验不能编译

package org.blackice.news;import com.opensymphony.xwork2.ActionSupport;public class Login extends ActionSupport {    static final long serialVersionUID = 5465432167631354L;    private String username;    private String password;        public String getUsername(){        return this.username;    }    public void setUsername(String username){        this.username = username;    }    public String getPassword(){        return this.password;    }    public void setPassword(String password){        this.password = password;    }    public String execute(){        if(this.getUsername()==null||this.getUsername().equals("")){            this.addFieldError("username", "请输入用户名");            return INPUT;        }        if(this.getPassword()==null||this.getPassword().equals("")){            this.addFieldError("password", "请输入密码");            return INPUT;        }        return SUCCESS;    }    public void validate(){        if(this.getUsername()==null||this.getUsername().equals("")){            this.addFieldError("username", "请输入用户名");        }        if(this.getPassword()==null||this.getPassword().equals("")){            this.addFieldError("password", "请输入密码");        }    }}

<!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="username">       <field-validator type="requiredstring">            <param name="trim">true</param>            <message>User</message>       </field-validator>    </field>    <field name="password">       <field-validator type="requiredstring">            <param name="trim">true</param>            <message>pass</message>       </field-validator>    </field></validators>

"-//Apache Software Foundation//DTD Struts Configuration 2.0//EN""http://struts.apache.org/dtds/struts-2.0.dtd"><struts><constant name="struts.custom.i18n.resources" value="messageResource"></constant><package name="org.blackice.news" extends="struts-default">    <action name="HelloWorld" class="org.blackice.news.HelloWorld">        <result>/HelloWorld.jsp</result>    </action>    <action name="Login" class="org.blackice.news.Login">        <result name="input">Login.jsp</result>        <result name="success">index</result>    </action></package></struts>

<?xml version="1.0" encoding="UTF-8"?><!DOCTYPE validators PUBLIC        "-//OpenSymphony Group//XWork Validator Config 1.0//EN"        "http://www.opensymphony.com/xwork/xwork-validator-config-1.0.dtd"><!-- START SNIPPET: validators-default --><validators>    <validator name="required" class="com.opensymphony.xwork2.validator.validators.RequiredFieldValidator"/>    <validator name="requiredstring" class="com.opensymphony.xwork2.validator.validators.RequiredStringValidator"/>    <validator name="int" class="com.opensymphony.xwork2.validator.validators.IntRangeFieldValidator"/>    <validator name="long" class="com.opensymphony.xwork2.validator.validators.LongRangeFieldValidator"/>    <validator name="short" class="com.opensymphony.xwork2.validator.validators.ShortRangeFieldValidator"/>    <validator name="double" class="com.opensymphony.xwork2.validator.validators.DoubleRangeFieldValidator"/>    <validator name="date" class="com.opensymphony.xwork2.validator.validators.DateRangeFieldValidator"/>    <validator name="expression" class="com.opensymphony.xwork2.validator.validators.ExpressionValidator"/>    <validator name="fieldexpression" class="com.opensymphony.xwork2.validator.validators.FieldExpressionValidator"/>    <validator name="email" class="com.opensymphony.xwork2.validator.validators.EmailValidator"/>    <validator name="url" class="com.opensymphony.xwork2.validator.validators.URLValidator"/>    <validator name="visitor" class="com.opensymphony.xwork2.validator.validators.VisitorFieldValidator"/>    <validator name="conversion" class="com.opensymphony.xwork2.validator.validators.ConversionErrorFieldValidator"/>    <validator name="stringlength" class="com.opensymphony.xwork2.validator.validators.StringLengthFieldValidator"/>    <validator name="regex" class="com.opensymphony.xwork2.validator.validators.RegexFieldValidator"/>    <validator name="conditionalvisitor" class="com.opensymphony.xwork2.validator.validators.ConditionalVisitorFieldValidator"/></validators>