struts2--详细了解struts2框架的校验器

港控/mmm° 2024-02-18 14:13 7阅读 0赞

和拦截器一样，struts2提供了内置校验器。在/com/opensymphony/xwork2/validator/validators/default.xml下。具体如：

default.xml:

<?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">
    
    
    <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>

1、转换校验器（conversion）：

字段校验风格：

<validators>
        <field name = "user.age">
        <field-validator type = "conversion">
           <param name = "repoplateField">true</param>
           <message>你的年龄必须是一个整数</message>
        </field-validator> 
      </field>
    </validators>

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非字段校验器配置风格：

<validators>
        <validator type = "conversion">
           <param name = "fieldName">user.age</param>
           <param name = "repoplateField">false</param>
           <message>你的年龄必须是一个整数</message>
      </validator>
    </validators>

2、邮件地址校验器(email)：

<field name = "user.email">
        <field-validator type = "email">
           <message>您的邮件格式不正确</message>
        </field-validator> 
      </field>

3、网址校验器(url)：

<field name = "字段名">
        <field-validator type = "url">
           <message>提示错误信息</message>
        </field-validator> 
      </field>

4、表达式校验器（expression）：（不可用在字段校验确配置风格中）

表达式校验器的名字：expression，它是一个非字段校验器， 不可在字段校验器中使用它，该表达式要求OGNL表达式返回TRUE；当返回TRUE时，该校验通过，否则就算该校验没有通过！

参数：

1.  expression： 该参数指定一个逻辑表达式，该逻辑表达式基于ValueStack进行求值，最后返回一个Boolean值，当返回TRUE时校验通过，否则校验失败

<validator type = "expression">
         <param name = "expression">……</param>
         <message>提示错误信息</message>
      </validator>

5、必填校验器（required）:检查字段必须有值(null)

<field name="user.password">
    		<field-validator type="required">
    			<message>请输入密码</message>
    		</field-validator>
    	</field>

由于是和null作比较，而表单提交的是字符串，当不填写任何内容时为""，导致无法达到效果。当表单提交没有此字段时为null，如：

debug看结果：

![Center 1][]

6、字符串长度校验器(requiredstring)：

<field name="user.username">
    		<field-validator type="requiredstring">
    			<param name="doTrim">true</param>      
    			<message>用户名不能为空</message>
    		</field-validator>
    	</field>

7、整数校验器（int）：

<field name = "user.age">
        <field-validator type = "int">
           <param name = "min">1</param>
           <param name = "max">100</param>
           <message>输入的年龄必须在1-100之间</message>
        </field-validator> 
      </field>

8、日期校验类型（date）

<field name = "user.birthday">
        <field-validator type = "date">
           <param name = "min">1990-01-01</param>
           <param name = "max">2020-01-01</param>
           <message>请正确输入生日</message>
         </field-validator> 
      </field>

9、字段表达式校验器（fieldexpression）

<field name="user.repassword">
    		<field-validator type="fieldexpression">
    		    <param name = "expression"><![CDATA[user.password==user.repassword]]></param>
    			<message>两次密码不一致</message>
    		</field-validator>
    	</field>

10、正则表达式校验器（regex)

<field name = "user.password">
        <field-validator type = "regex">
           <param name = "expression"><![CDATA[(\w{6})]]></param>
           <message>${getText("user.password.regex")}</message>
        </field-validator> 
      </field>

11、visitor校验器：

该属性用于检测Action里的复合属性（如User对象等）以User对象为例说明：

LoginAction.java:

package com.action;
    
    import com.bean.User;
    import com.opensymphony.xwork2.ActionSupport;
    
    public class LoginAction extends ActionSupport{
     private User user;
     public String execute() {
    	return SUCCESS;
    }
    public User getUser() {
    	return user;
    }
    
    public void setUser(User user) {
    	this.user = user;
    }
     
    }

LoginAction-validation.xml配置文件：

<?xml version="1.0" encoding="UTF-8"?>
      <!DOCTYPE validators PUBLIC
      		"-//OpenSymphony Group//XWork Validator 1.0.3//EN"
      		"http://www.opensymphony.com/xwork/xwork-validator-1.0.3.dtd">
    
    <validators>
    
      <field name = "user"> 
         <field-validator type = "visitor">
         
             <param name = "context">userContext</param>
             
             <param name = "appendPrefix">true</param>
             <message>用户的：</message>
         </field-validator>
      </field>
    </validators>

为User属性配置单独的校验文件，默认的文件名应为User-validation.xml，因为在LoginAction-validation.xml文件中指明了visitor的context属性userContext，因此校验文件名应为User-userContext-validation.xml：

该配置文件需要和User.java在同一目录下，否则校验器不起作用  
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[Center]: https://image.dandelioncloud.cn/pgy_files/images/2024/01/29/a8d2d7f2f5cc4ef89f96310e5c16c1d3.png
[Center 1]: https://image.dandelioncloud.cn/pgy_files/images/2024/01/29/eb44f04098974e948a9be88988503446.png
[Center 2]: https://image.dandelioncloud.cn/pgy_files/images/2024/01/29/4398acb070d34916b6e4d0ee64d44777.png