[Java EE] Three-tier architecture case-user module (i)

User Registration Login Logout

servlet+jsp+javabean+dom4j

Hierarchical structure:

Com.tsh.web

Com.tsh.service

Com.tsh.dao

Com.tsh.domain

Com.tsh.util

Com.tsh.test

Com.tsh.exception

Com.tsh.factory

Packages used:

dom4j Jstl beanutils JUnit

Users.xml----------- Simulation Database

Config.properties------------The main configuration file

XPATH:

DOM4J provides a way to find the specified node in the XML file, similar to the regular lookup of the specified text in a text file

Com.tsh.dao.XmlUserDao.java

 PackageCom.tsh.dao;Importjava.util.List;Importorg.dom4j.Document;ImportOrg.dom4j.DocumentHelper;Importorg.dom4j.Element;ImportCom.tsh.domain.User;ImportCom.tsh.util.XmlDaoUtil; Public classXmluserdao {/*** Find User by username *@paramusername *@return     */     PublicUser Finduserbyusername (String username) {Document Dom=Xmldaoutil.getdom (); Element Root=dom.getrootelement (); //using the XPath syntaxList<element> list=root.selectnodes ("//user[@username = '" +username+ "']"); if(List.size () >0) {Element userelement=list.get (0); String uname=userelement.attributevalue ("username"); String Password=userelement.attributevalue ("Password"); //encapsulating user information into a beanUser user=NewUser ();            User.setusername (uname);            User.setpassword (password);            User.setpassword_confirm (password); returnuser; }        return NULL; }    /*** Add User *@paramUser*/     Public voidaddUser (user user) {Document Dom=Xmldaoutil.getdom (); Element Root=dom.getrootelement (); //Create <user> elementsElement userelement=documenthelper.createelement ("User"); Userelement.setattributevalue ("Username", User.getusername ()); Userelement.setattributevalue ("Password", User.getpassword ()); //Mount to <users>Root.add (userelement); //write back to XML file            }}

Com.tsh.util.XmlDaoUtil.java

 PackageCom.tsh.util;ImportJava.net.URL;Importorg.dom4j.Document;ImportOrg.dom4j.io.SAXReader; Public classXmldaoutil {Private StaticURL Path=xmldaoutil.class. getClassLoader (). GetResource ("User.xml"); /*** Using static code blocks, objects are instantiated only once*/    Private StaticDocument Dom; Static{Saxreader Reader=NewSaxreader (); Try {            //class loader finds physical pathDom=reader.read (path); } Catch(Exception e) {e.printstacktrace (); }    }    /*** Get XML *@return     */     Public StaticDocument GetDOM () {returnDom; }    /*** Write XML*/     Public Static voidwriteXml () {}}

Com.tsh.domain.User.java

 PackageCom.tsh.domain;Importjava.io.Serializable; Public classUserImplementsserializable{PrivateString username; PrivateString password; PrivateString password_confirm;  PublicString GetUserName () {returnusername; }     Public voidSetusername (String username) { This. Username =username; }     PublicString GetPassword () {returnpassword; }     Public voidSetPassword (String password) { This. Password =password; }     PublicString getpassword_confirm () {returnpassword_confirm; }     Public voidsetpassword_confirm (String password_confirm) { This. password_confirm =password_confirm; }    }

User.xml

<? XML version= "1.0" encoding= "UTF-8" ?> < Users > <  username= "admin"  password= "admin"></User  ></users>

[Java EE] Three-tier architecture case-user module (i)