struts2表单数据验证

野性酷女 2022-06-13 05:26 213阅读 0赞

struts2的表单数据需要进行验证，验证有两种，一种是手动在action的方法中验证，另一种是使用框架的xml配置文件验证。

# 一、手动action中验证 #

程序架构图：

![Center][]

表单页面register.jsp代码：

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
    <%@ taglib prefix="s" uri="/struts-tags" %>
    <%
    String path = request.getContextPath();
    String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
    %>
    
    <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
    <html>
      <head>
        <base href="<%=basePath%>">
        
        <title>My JSP 'register.jsp' starting page</title>
        
    	<meta http-equiv="pragma" content="no-cache">
    	<meta http-equiv="cache-control" content="no-cache">
    	<meta http-equiv="expires" content="0">    
    	<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
    	<meta http-equiv="description" content="This is my page">
    	
    
      </head>
      
      <body>
      <s:actionerror/>
           <form action="register.action" method="post">
    			用户名：<input type="text" name="name" /><br/>
    			密码：<input type="password" name="pwd" /><br/>
    			年龄：<input type="text" name="age" /><br/>
    			生日:<input type="text" name="birthday" /><br/>
    			<input type="submit" value="登陆" />       
           </form>
      </body>
    </html>

RegisterAction.java代码：

package com.robert.validate.action;
    
    import java.util.Date;
    
    import com.opensymphony.xwork2.ActionSupport;
    
    public class RegisterAction extends ActionSupport {
    
    	private String name;
    	private String pwd;
    	private int age;
    	private Date birthday;
    
    	public String register() {
    		System.out.println("register...");
    		return SUCCESS;
    	}
    
    	/**
    	 * 这里的validateRegister()方法中的register是上面的register()方法,
    	 * 也就是struts.xml配置文件中的action中的method对应的register方法,
    	 * 当程序执行method为register的方法时,就会先执行validateRegister()验证方法,
    	 * 然后执行validate()方法,最后执行register()方法.
    	 */
    	public void validateRegister() {
    		System.out.println("validateRegister...age=" + age);
    		if (age > 100 || age < 1) {
    			this.addActionError("年龄不合法");
    		}
    	}
    
    	/**
    	 * 程序先执行validate（）方法，然后在执行register()方法
    	 */
    	@Override
    	public void validate() {
    		System.out.println("validate...name=" + name);
    		if (name != null && (name.length() < 5 || name.length() > 10)) {
    			this.addActionError("姓名不为空，且长度必须大于5,小于10");
    		}
    	}
    
    	public String getName() {
    		return name;
    	}
    
    	public void setName(String name) {
    		this.name = name;
    	}
    
    	public int getAge() {
    		return age;
    	}
    
    	public void setAge(int age) {
    		this.age = age;
    	}
    
    	public String getPwd() {
    		return pwd;
    	}
    
    	public void setPwd(String pwd) {
    		this.pwd = pwd;
    	}
    
    	public Date getBirthday() {
    		return birthday;
    	}
    
    	public void setBirthday(Date birthday) {
    		this.birthday = birthday;
    	}
    
    }

struts.xml配置文件代码

<?xml version="1.0" encoding="UTF-8" ?>
    
    <!DOCTYPE struts PUBLIC
        "-//Apache Software Foundation//DTD Struts Configuration 2.3//EN"
        "http://struts.apache.org/dtds/struts-2.3.dtd">
    
    <struts>
    	<package name="default" namespace="/" extends="struts-default">
    		<action name="register" class="com.robert.validate.action.RegisterAction"
    			method="register">
    			<result>/index.jsp</result>
    			
    			<result name="input">/register.jsp</result>
    		</action>
    	</package>
    </struts>

打开浏览器输入url：http://localhost:8080/validate/register.jsp

输入数据：name=ad ,age=-11

![Center 1][]

点击登陆按钮，如图：

![Center 2][]

上面显示的提示信息就是在Action类中手动写的表单数据验证。

# 二、框架xml文件验证 #

项目架构截图：

![Center 3][]

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
    <%@ taglib prefix="s" uri="/struts-tags" %>
    <%
    String path = request.getContextPath();
    String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
    %>
    
    <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
    <html>
      <head>
        <base href="<%=basePath%>">
        
        <title>My JSP 'register.jsp' starting page</title>
        
    	<meta http-equiv="pragma" content="no-cache">
    	<meta http-equiv="cache-control" content="no-cache">
    	<meta http-equiv="expires" content="0">    
    	<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
    	<meta http-equiv="description" content="This is my page">
    	
    
      </head>
      
      <body>
     
      <s:fielderror />
           <form action="register.action" method="post">
    			用户名：<input type="text" name="name" /><br/>
    			密码：<input type="password" name="pwd" /><br/>
    			年龄：<input type="text" name="age" /><br/>
    			生日:<input type="text" name="birthday" /><br/>
    			<input type="submit" value="登陆" />       
           </form>
      </body>
    </html>

RegisteValidateAction.java代码：

package com.robert.validate.action;
    
    import java.util.Date;
    
    import com.opensymphony.xwork2.ActionSupport;
    
    public class RegisterValidateAction extends ActionSupport {
    
    	private String name;
    	private String pwd;
    	private int age;
    	private Date birthday;
    
    	public String register() {
    		System.out.println("register...");
    		return SUCCESS;
    	}
    
    	public String getName() {
    		return name;
    	}
    
    	public void setName(String name) {
    		this.name = name;
    	}
    
    	public int getAge() {
    		return age;
    	}
    
    	public void setAge(int age) {
    		this.age = age;
    	}
    
    	public String getPwd() {
    		return pwd;
    	}
    
    	public void setPwd(String pwd) {
    		this.pwd = pwd;
    	}
    
    	public Date getBirthday() {
    		return birthday;
    	}
    
    	public void setBirthday(Date birthday) {
    		this.birthday = birthday;
    	}
    
    }

使用struts2框架的验证规则是：每一个action对应一个验证xml文件，xml文件格式是： ActionName-validation.xml

此项目中的xml配置文件是：RegisterValidateAction-validation.xml，代码：

<?xml version="1.0" encoding="UTF-8"?>
    <!DOCTYPE validators PUBLIC "-//Apache Struts//XWork Validator 1.0.3//EN"
            "http://struts.apache.org/dtds/xwork-validator-1.0.3.dtd">
            
    <validators>
    	<field name="name">
    		<field-validator type="requiredstring">
    			<param name="trim">true</param>
    			<message>name is required(用户名必填)</message>
    		</field-validator>
    	</field>
    </validators>

这里只写了一个表单用户名name的验证，

struts.xml的代码是：

<?xml version="1.0" encoding="UTF-8" ?>
    
    <!DOCTYPE struts PUBLIC
        "-//Apache Software Foundation//DTD Struts Configuration 2.3//EN"
        "http://struts.apache.org/dtds/struts-2.3.dtd">
    
    <struts>
    	<package name="default" namespace="/" extends="struts-default">
    		<action name="register"
    			class="com.robert.validate.action.RegisterValidateAction" method="register">
    			<result>/index.jsp</result>
    			
    			<result name="input">/register.jsp</result>
    		</action>
    	</package>
    </struts>

浏览器中输入URL：http://localhost:8080/validate/register.jsp

![Center 4][]

点击登陆按钮,验证未通过，仍然返回register.jsp页面，展示验证结果：

![Center 5][]

# 下面介绍一下怎么样配置ActionName-validation.xml文件 #

根据struts2自带的docs文档，

##    根据docs文档： ##

从struts2官网上下载struts的压缩包，我下载的是struts-2.3.32-all.zip，解压后，得到

struts-2.3.32-all ，然后依次点击进入：struts-2.3.32-->docs-->docs,找到index.html文件，

在浏览器中打开，如图：

![Center 6][]

进入Guides，

![Center 7][]

进入Validation页面后，一直往下来，可以看到Registering Validators，如图：

![Center 8][]

这部分介绍了，struts2框架自带的验证的类型，对应的class是实现这个类型的源码，我们就拿我们项目demo中使

用的requiredstring验证为例，来看看源码，

![Center 9][]

点击上图的xwork-core-2.3.32.jar包，进入，在com.opensymphony.xwork2.validator.validators包下找到

RequiredStringValidator.class文件，如图：

![Center 10][]

RequiredStringValidator.class源码如下：

/*
     * Copyright 2002-2006,2009 The Apache Software Foundation.
     * 
     * Licensed under the Apache License, Version 2.0 (the "License");
     * you may not use this file except in compliance with the License.
     * You may obtain a copy of the License at
     * 
     *      http://www.apache.org/licenses/LICENSE-2.0
     * 
     * Unless required by applicable law or agreed to in writing, software
     * distributed under the License is distributed on an "AS IS" BASIS,
     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     * See the License for the specific language governing permissions and
     * limitations under the License.
     */
    package com.opensymphony.xwork2.validator.validators;
    
    import com.opensymphony.xwork2.validator.ValidationException;
    
    
    /**
     * 
     * RequiredStringValidator checks that a String field is non-null and has a length > 0.
     * (i.e. it isn't "").  The "trim" parameter determines whether it will {@link String#trim() trim}
     * the String before performing the length check.  If unspecified, the String will be trimmed.
     * 
     * <p/>
     *
     * 
     * <ul>
     * 		<li>fieldName - The field name this validator is validating. Required if using Plain-Validator Syntax otherwise not required</li>
     *      <li>trim - (Optional) Boolean, default true. Trims the field name value before validating.</li>
     *      <li>trimExpression - (Optional) String. Specifies the trim param as an OGNL expression.</li>
     * </ul>
     * 
     * 
     * 
     * Do not use ${trimExpression} as an expression as this will turn into infinitive loop!
     * 
     *
     * <pre>
     * 
     *     <validators>
     *         
     *         <validator type="requiredstring">
     *             <param name="fieldName">username</param>
     *             <param name="trim">true</param>
     *             <message>username is required</message>
     *         </validator>
     *         
     *         
     *         <field name="username">
     *         	  <field-validator type="requiredstring">
     *                 <param name="trim">true</param>
     *                 <message>username is required</message>
     *            </field-validator>
     *         </field>
     *
     *         
     *         <field name="username">
     *         	  <field-validator type="requiredstring">
     *                 <param name="trimExpression">${trimValue}</param> 
     *                 <message>username is required</message>
     *            </field-validator>
     *         </field>
     *     </validators>
     * 
     * </pre>
     * 
     * @author rainerh
     * @version $Date$ $Id$
     */
    public class RequiredStringValidator extends FieldValidatorSupport {
    
        private boolean trim = true;
    
        public void setTrim(boolean trim) {
            this.trim = trim;
        }
    
        public void setTrimExpression(String trimExpression) {
            trim = (Boolean) parse(trimExpression, Boolean.class);
        }
    
        public boolean isTrim() {
            return trim;
        }
    
        public void validate(Object object) throws ValidationException {
            String fieldName = getFieldName();
            Object value = this.getFieldValue(fieldName, object);
    
            if (!(value instanceof String)) {
                addFieldError(fieldName, object);
            } else {
                String s = (String) value;
    
                if (trim) {
                    s = s.trim();
                }
    
                if (s.length() == 0) {
                    addFieldError(fieldName, object);
                }
            }
        }
    
    }

其中有一点注释掉的内容，就是举例子告诉我们怎么写配置文件，

![Center 11][]

翻译成xml文件格式就是：

<validators>
    	<field name="name">
    		<field-validator type="requiredstring">
    			<param name="trim">true</param>
    			<message>name is required(用户名必填)</message>
    		</field-validator>
    	</field>
    </validators>

继续看源码中，只有一个属性，trim，如图：

![Center 12][]

继续读取文档，可以看到文档中举了一些例子，告诉我们常见的该怎么配置，如图：

![Center 13][]

文档中没有的例子，可以按照按照上面的方法，从源码中寻找，每一个源码中都有例子。一共有16个类型

![Center 14][]

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