Struts

 <?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5" 
xmlns="http://java.sun.com/xml/ns/javaee" 
xmlns:xsi="http://www.w3.org/2001
/XMLSchema-instance" 
xsi:schemaLocation="http://java.sun.com
/xml/ns/javaee 
http://java.sun.com/xml/ns/javaee
/web-app_2_5.xsd">
  <filter>
  <filter-name>f1</filter-name>
  <filter-class>org.apache.struts2.dispatcher
  .FilterDispatcher</filter-class>
  </filter>
  <filter-mapping>
  <filter-name>f1</filter-name>
  <url-pattern>/*</url-pattern>
  </filter-mapping>
</web-app>

<%@taglib uri="/struts-tags" prefix="s"%>
<s:form action="register">
<s:textfield name="name" label="Name"/>
<s:password name="password" label="Password"/>
<s:textfield name="mailId" label="MailId"/>
<s:submit value="Register"/>
</s:form>

package mypack;
import com.opensymphony.xwork2.ActionSupport;
public class RegisterAction extends
	ActionSupport {
	private String name,password,mailId;
@Override
	public void validate(){
	if(name.length()==0)
		this.addFieldError("name",
		getText("name.required"));
	if(password.length()==0)
		this.addFieldError("password",
		getText("password.required"));
	if(password.length()<5)
		this.addFieldError("password",
		getText("password.length"));
}
public String execute(){
	return "success";
}
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public String getPassword() {
		return password;
	}
	public void setPassword(String password) {
		this.password = password;
	}
	public String getMailId() {
		return mailId;
	}
	public void setMailId(String mailId) {
		this.mailId = mailId;
	}
}

 name.required=Name is required
password.required=Password is required
password.length=Password must contain
at least 5 character

name.required=Nameam ke bina kam nahi chalaga
password.required=Password ke bina nahi chalaga
password.length=Password kam se kam 5 character
hona chahiye

<!DOCTYPE struts PUBLIC"-
//Apache Software Foundation
//DTD StrutsConfiguration 2.0//EN" 
"http://struts.apache.org/dtds/struts-2.0.dtd">
<struts>
 <package name="demo" extends="struts-default">
 <action name="register" 
 class="mypack.RegisterAction">
 <result name="success">/hello.jsp</result>
 <result name="input">/index.jsp</result>
 </action>
 </package>
 </struts>

<%@ taglib  uri="/struts-tags" prefix="s"%>
<b>You are successfully registered