工程如图：
Java代码：
package com.struts2.action;
import com.opensymphony.xwork2.ActionSupport;
public class LoginAction extends ActionSupport {
private static final long serialVersionUID = 1L;
private String username;
private String password;
private String message;
@Override
public String execute() throws Exception {
if ("scott".equals(username) && "tiger".equals(password)) {
setMessage("login succeed");
return SUCCESS;
} else {
setMessage("login failed");
return ERROR;
}
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public String getMessage() {
return message;
}
public void setMessage(String message) {
this.message = message;
}
}
LoginAction-validation.xml：
<!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="username">
<field-validator type="requiredstring">
<message key="requiredstring" />
</field-validator>
</field>
<field name="password">
<field-validator type="requiredstring">
<message key="requiredstring" />
</field-validator>
</field>
</validators>
struts.xml：
<?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="login" class="com.struts2.action.LoginAction">
<result name="input">login.jsp</result>
<result name="success">success.jsp</result>
<result name="error">error.jsp</result>
</action>
</package>
</struts>
package.properties：
HelloWorld.message= Struts is up and running ...
requiredstring = ${getText(fieldName)} is required.
password = Password
username = User Name
Missing.message = This feature is under construction. Please try again in the next interation.
log4j.properties：
#
# Log4J Settings for log4j 1.2.x (via jakarta-commons-logging)
#
# The five logging levels used by Log are (in order):
#
# 1. DEBUG (the least serious)
# 2. INFO
# 3. WARN
# 4. ERROR
# 5. FATAL (the most serious)
# Set root logger level to WARN and append to stdout
log4j.rootLogger=stdout
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.Target=System.out
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
# Pattern to output the caller's file name and line number.
log4j.appender.stdout.layout.ConversionPattern=%d %5p (%c:%L) - %m%n
# Print only messages of level ERROR or above in the package noModule.
log4j.logger.noModule=FATAL
log4j.logger.com.opensymphony.xwork2=DEBUG
log4j.logger.org.apache.struts2=DEBUG
web.xml：
<?xml version="1.0" encoding="UTF-8"?>
<web-app id="WebApp_9" 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">
<display-name>Struts Blank</display-name>
<filter>
<filter-name>struts2</filter-name>
<filter-class>org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>struts2</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<welcome-file-list>
<welcome-file>index.html</welcome-file>
<welcome-file>index.htm</welcome-file>
<welcome-file>index.jsp</welcome-file>
<welcome-file>default.html</welcome-file>
<welcome-file>default.htm</welcome-file>
<welcome-file>default.jsp</welcome-file>
</welcome-file-list>
</web-app>
login.jsp：
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<%@ taglib prefix="s" uri="/struts-tags"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
<s:form action="login">
<s:textfield key="username" label="username" />
<s:password key="password" label="password" />
<s:submit />
</s:form>
</body>
</html>
在xwork-core的jar包里，有个文件，在com.opensymphony.xwork2.validator.validators里，default.xml：
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE validators PUBLIC
"-//Apache Struts//XWork Validator Definition 1.0//EN"
"http://struts.apache.org/dtds/xwork-validator-definition-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>
<!-- END SNIPPET: validators-default -->
上面就是一些校验器。