]]>
?/span>Struts2中最单的验证数据的方法是使用validate。我们从ActionSupportcȝ源代码中可以看到Q?/span>ActionSupportcdC一?/span>Validateable接口。这个接口只有一?/span>validateҎ。如?/span>ActioncdCq个接口Q?/span>Struts2在调?/span>executeҎ之前首先会调用这个方法，我们可以?/span>validateҎ中验证，如果发生错误Q可以根据错误的level选择字段U错误，q是动作U错误。ƈ且可使用addFieldError?/span>addActionError加入相应的错误信息，如果存在Action?/span>Field错误Q?/span>Struts2会返?#8220;input”Q这个ƈ不用开发h员写Q由Struts2自动q回Q，如果q回?#8220;input”Q?/span>Struts2׃会再调用executeҎ了。如果不存在错误信息Q?/span>Struts2在最后会调用executeҎ?/span>
q两?/span>addҎ?/span>ActionErrorscM?/span>addҎcMQ只?/span>addҎ的错误信息需要一?/span>ActionMessage对象Q比较麻烦。除了加入错误信息外Q还可以使用addActionMessageҎ加入成功提交后的信息。当提交成功后，可以昄q些信息?/span>
以上三个addҎ都在ValidationAware接口中定义，q且?/span>ActionSupportcM有一个默认的实现。其实，?/span>ActionSupportcM的实现实际上是调用了ValidationAwareSupport中的相应的方法，也就是这三个addҎ是在ValidationAwareSupportcM实现的，代码如下Q?br />private final ValidationAwareSupport validationAware = new ValidationAwareSupport();
public void addActionError(String anErrorMessage)
{ validationAware.addActionError(anErrorMessage);
}
public void addActionMessage(String aMessage)
{
validationAware.addActionMessage(aMessage);
}
public void addFieldError(String fieldName, String errorMessage)
{
validationAware.addFieldError(fieldName, errorMessage);
}
public void addActionError(String anErrorMessage)
{ validationAware.addActionError(anErrorMessage);
}
public void addActionMessage(String aMessage)
{
validationAware.addActionMessage(aMessage);
}
public void addFieldError(String fieldName, String errorMessage)
{
validationAware.addFieldError(fieldName, errorMessage);
}
下面我们来实C个简单的验证E序Q来体验一?/span>validateҎ的用?/span>
先来?/span>Web根目录徏立一个主面Q?/span>validate.jspQ，代码如下Q?/span>
<%@ page language="java" import="java.util.*" pageEncoding="GBK"%>
<%@ taglib prefix="s" uri="/struts-tags" %>
<html>
<head>
<title>验证数据</title>
</head>
<body>
<s:actionerror/>
<s:actionmessage/>
<s:form action="validate.action" theme="simple">
输入内容Q?/span><s:textfield name="msg"/>
<s:fielderror key="msg.hello" />
<br/>
<s:submit/>
</s:form>
</body>
</html>
<%@ taglib prefix="s" uri="/struts-tags" %>
<html>
<head>
<title>验证数据</title>
</head>
<body>
<s:actionerror/>
<s:actionmessage/>
<s:form action="validate.action" theme="simple">
输入内容Q?/span><s:textfield name="msg"/>
<s:fielderror key="msg.hello" />
<br/>
<s:submit/>
</s:form>
</body>
</html>
在上面的代码中，使用?/span>Struts2?/span>tagQ?/span><s:actionerror>?/span><s:fielderror>?/span><s:actionmessage>Q分别用来显C动作错误信息，字段错误信息Q和动作信息。如果信息ؓI，则不昄?/span>
现在我们来实C个动作类Q代码如下：
package action;
import javax.servlet.http.*;
import com.opensymphony.xwork2.ActionSupport;
import org.apache.struts2.interceptor.*;
public class ValidateAction extends ActionSupport
{
private String msg;
public String execute()
{
System.out.println(SUCCESS);
return SUCCESS;
}
public void validate()
{
if(!msg.equalsIgnoreCase("hello"))
{
System.out.println(INPUT);
this.addFieldError("msg.hello", "必须输入hello!");
this.addActionError("处理动作p|!");
}
else
{
this.addActionMessage("提交成功");
}
}
public String getMsg()
{
return msg;
}
public void setMsg(String msg)
{
this.msg = msg;
}
}
import javax.servlet.http.*;
import com.opensymphony.xwork2.ActionSupport;
import org.apache.struts2.interceptor.*;
public class ValidateAction extends ActionSupport
{
private String msg;
public String execute()
{
System.out.println(SUCCESS);
return SUCCESS;
}
public void validate()
{
if(!msg.equalsIgnoreCase("hello"))
{
System.out.println(INPUT);
this.addFieldError("msg.hello", "必须输入hello!");
this.addActionError("处理动作p|!");
}
else
{
this.addActionMessage("提交成功");
}
}
public String getMsg()
{
return msg;
}
public void setMsg(String msg)
{
this.msg = msg;
}
}
大家从上面的代码可以看出Q?/span>Field错误需要一?/span>keyQ一般用来表C是哪一个属性出的错误）Q?/span>Action错误?/span>Action消息只要提供一个信息字W串可以了?/span>
最后来配置一下这?/span>ActionQ代码如下：
<package name="demo" extends="struts-default">
<action name="validate" class="action.ValidateAction">
<result name="success">/error/validate.jsp</result>
<result name="input">/error/validate.jsp</result>
</action>
</package>
<action name="validate" class="action.ValidateAction">
<result name="success">/error/validate.jsp</result>
<result name="input">/error/validate.jsp</result>
</action>
</package>
假设应用E序的上下文路径?/span>demoQ则可通过如下?/span>URL来测试程序：
http://localhost:8080/demo/validate.jsp
我们q可以?/span>ValidationAware接口的其他方法（?/span>ValidationAwareSupportcd玎ͼ获得或设|字D错误信息、动作错误信息以及动作消息。如hasActionErrorsҎ判断是否存在动作层的错误Q?/span>getFieldErrors获得字段错误信息Q一?/span>Map对象Q。下面是ValidationAware接口提供的所有的ҎQ?/span>
package com.opensymphony.xwork2;
import java.util.Collection;
import java.util.Map;
public interface ValidationAware
{
void setActionErrors(Collection errorMessages);
Collection getActionErrors();
void setActionMessages(Collection messages);
Collection getActionMessages();
void setFieldErrors(Map errorMap);
Map getFieldErrors();
void addActionError(String anErrorMessage);
void addActionMessage(String aMessage);
void addFieldError(String fieldName, String errorMessage);
boolean hasActionErrors();
boolean hasActionMessages();
boolean hasErrors();
boolean hasFieldErrors();
}
import java.util.Collection;
import java.util.Map;
public interface ValidationAware
{
void setActionErrors(Collection errorMessages);
Collection getActionErrors();
void setActionMessages(Collection messages);
Collection getActionMessages();
void setFieldErrors(Map errorMap);
Map getFieldErrors();
void addActionError(String anErrorMessage);
void addActionMessage(String aMessage);
void addFieldError(String fieldName, String errorMessage);
boolean hasActionErrors();
boolean hasActionMessages();
boolean hasErrors();
boolean hasFieldErrors();
}
]]>
]]>
五个struts2必备jar?可以?a >http://www.struts.apache.org下蝲最新的struts2,struts2采用qo器org.apache.struts2.dispatcher.FilterDispatcher来过滤客L发送给服务器的所有请求。struts2.0是strtus1.*与webwork的结合。struts2.0会自动到工程下classes下寻找struts.xml(struts2.0的配|文?来解析配|的action{东东。废话少_代码如下Q?br /> 开发步?
1?下蝲struts2.0q添加核心jar?br /> 2、写面
index.jsp
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%><html> <head> <title>struts的Hello WorldE序</title> </head> <body> <form name='testform' method='post' action="login.action"> 用户名：<input name='username'><br> 密码Q?amp;nbsp; <input name='pwd' type='password'><br> <input type='submit' value=' ?nbsp; ?nbsp;'> <input type='reset' value=' ?nbsp; |?nbsp;'> </form> </body></html>show.jsp
<%@ page language="java" pageEncoding="UTF-8"%><html><head> <title>昄l果</title></head><body> <h3>用户?-->${requestScope.username}<br> 密码--->${requestScope.pwd}<br></body></html>3、写action
package com.yz.struts2.actions;
public class loginAction {
private String username; private String pwd;
public String getUsername() {
return username;
} public void setUsername(String username) { this.username = username; } public String getPwd() { return pwd; } public void setPwd(String pwd) { this.pwd = pwd; } public String helloWorld(){ System.out.println("用户?-->"+username); System.out.println("密码--->"+pwd); return "ok"; //查找名字为ok的resultQ相当于struts1.*的foward?/span> }
}4、配|struts2.0开发环?--struts.xml和web.xml
web.xml
<?xml version="1.0" encoding="UTF-8"?><web-app version="2.4" xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd"> <!-- struts2采用qo器过滤客L发送给服务器的所有请?nbsp;--> <filter> <filter-name>struts2</filter-name> <filter-class> org.apache.struts2.dispatcher.FilterDispatcher </filter-class> </filter> <filter-mapping> <filter-name>struts2</filter-name> <url-pattern>/*</url-pattern> </filter-mapping> <welcome-file-list> <welcome-file>index.jsp</welcome-file> </welcome-file-list></web-app><?xml version="1.0" encoding="UTF-8" ?><!DOCTYPE struts PUBLIC "-//Apache Software Foundation//DTD Struts Configuration 2.0//EN" "http://struts.apache.org/dtds/struts-2.0.dtd"><struts><!-- struts2会自动到classes下找struts.xmlQ?br />
直接攑֜src下工具会自动把src下的文g~译到classes?nbsp;dtd头信息表C?nbsp;sturs为根标签--> <!-- struts2q个包承sturs2内置的包struts-default --> <package name="struts2" extends="struts-default"> <!-- 配置action nameQ?nbsp;对应index.jsp面中form的action= login.action 的login struts默认所有以点actionl尾的请求交lstruts处理Q因为承自webwork的特性，习惯于这栗?br />
class: action对应的类,包名点类名全路径(com.yz.struts2.loginAction) methodQ请求该action时自动执行的ҎQ如果没有配|默认执行executeҎ --> <action name="login" class="com.yz.struts2.actions.loginAction" method="helloWorld" converter="" > <!-- result默认的name为success --> <result name="ok">/show.jsp</result> </action> </package></struts>]]>