本文实例为大家分享了java用户注册功能，供大家参考，具体内容如下

主页面:

浏览器显示：

代码实现：

用户信息管理

用户注册:

姓名:

密码:

查看所有用户

注册功能：

浏览器显示：

1)注册成功：

2)注册失败：

代码实现:

package cn.hncu.user.servlet;

import java.io.IOException;

import java.io.PrintWriter;

import java.util.List;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import cn.hncu.user.dao.UserDao;

import cn.hncu.user.dao.UserDaoImpl;

import cn.hncu.user.domain.User;

public class RegServlet extends HttpServlet {

//注入

UserDao dao=new UserDaoImpl();

public void doGet(HttpServletRequest request, HttpServletResponse response)

throws ServletException, IOException {

List users=dao.queryAllUsers();

response.setContentType("text/html;charset=utf-8");

PrintWriter out = response.getWriter();

out.println(""-//W3C//DTD HTML 4.01 Transitional//EN\">");

out.println("");

out.println("

注册结果页面");

out.println("

");

out.println("

操作	姓名

for(User u:users){

out.println("

删除");

out.println("

"+u.getName()+"");

}

out.println("

");

out.println(" ");

out.println("");

out.flush();

out.close();

}

public void doPost(HttpServletRequest request, HttpServletResponse response)

throws ServletException, IOException {

request.setCharacterEncoding("utf-8");

String name=request.getParameter("name");

String pwd=request.getParameter("pwd");

User user=new User();

user.setName(name);

user.setPwd(pwd);

boolean boo=dao.reg(user);

response.setContentType("text/html;charset=utf-8");

PrintWriter out = response.getWriter();

out.println(""-//W3C//DTD HTML 4.01 Transitional//EN\">");

out.println("");

out.println("

注册结果页面");

out.println("

");

if(boo){

out.println("恭喜您("+name+")注册成功了...");

}else{

out.println("您("+name+")注册失败了...
用户名已存在,请换一个注册");

}

out.println("返回");

out.println(" ");

out.println("");

out.flush();

out.close();

}

}

查看所有用户功能:

浏览器显示：

代码实现： RegServlet类的doGet方法实现

删除操作功能：删除成功会重定向到主页面

代码实现：

package cn.hncu.user.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import cn.hncu.user.dao.UserDao;

import cn.hncu.user.dao.UserDaoImpl;

public class DelServlet extends HttpServlet {

public void doGet(HttpServletRequest request, HttpServletResponse response)

throws ServletException, IOException {

String id=request.getParameter("id");

// System.out.println("del-id:"+id);

UserDao dao=new UserDaoImpl();

dao.delUser(id);

//转到主页--重定向

response.sendRedirect("/usersWeb/index.jsp");

}

public void doPost(HttpServletRequest request, HttpServletResponse response)

throws ServletException, IOException {

doGet(request,response);

}

}

配置文件：

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_3_0.xsd">

RegServlet

cn.hncu.user.servlet.RegServlet

DelServlet

cn.hncu.user.servlet.DelServlet

RegServlet

/reg

DelServlet

/del

index.jsp

domain包的User对象

package cn.hncu.user.domain;

public class User {

private String id;

private String name;

private String pwd;

public String getName() {

return name;

}

public void setName(String name) {

this.name = name;

}

public String getPwd() {

return pwd;

}

public void setPwd(String pwd) {

this.pwd = pwd;

}

public String getId() {

return id;

}

public void setId(String id) {

this.id = id;

}

@Override

public int hashCode() {

final int prime = 31;

int result = 1;

result = prime * result + ((id == null) ? 0 : id.hashCode());

return result;

}

@Override

public boolean equals(Object obj) {

if (this == obj)

return true;

if (obj == null)

return false;

if (getClass() != obj.getClass())

return false;

User other = (User) obj;

if (id == null) {

if (other.id != null)

return false;

} else if (!id.equals(other.id))

return false;

return true;

}

@Override

public String toString() {

return "User [id=" + id + ", name=" + name + ", pwd=" + pwd + "]";

}

}

逻辑层dao：

接口

实现类

package cn.hncu.user.dao;

import java.util.ArrayList;

import java.util.List;

import org.dom4j.Document;

import org.dom4j.Element;

import org.dom4j.Node;

import cn.hncu.user.domain.User;

import cn.hncu.user.utils.DomFactory;

import cn.hncu.user.utils.IDGenerate;

public class UserDaoImpl implements UserDao{

Document dom=DomFactory.getDom();

@Override

public boolean reg(User user) {

// //title[@lang='eng']选取所有 title 元素，且这些元素拥有值为 eng 的 lang 属性。

// dom.selectSingleNode("//user[fn:lower-case(@name)='"+user.getName().toLowerCase()+"']");

Node node=dom.selectSingleNode("//user[name='"+user.getName()+"']");//user节点下值为user.getName()的name元素

//"name[='"+user.getName().toLowerCase()+"']"

if(node!=null){

return false;

}

Element root=dom.getRootElement();

Element eUser=root.addElement("user");

String id=IDGenerate.getID();

eUser.addAttribute("id", id);

eUser.addElement("name").setText(user.getName());

eUser.addElement("pwd").setText(user.getPwd());

DomFactory.save();

return true;

}

@Override

public List queryAllUsers() {

List users=new ArrayList();

List en=dom.selectNodes("//user");

for(Element e:en){

String id=e.attributeValue("id");

String name=e.elementText("name");

User user=new User();

user.setId(id);

user.setName(name);

users.add(user);

}

return users;

}

@Override

public void delUser(String id) {

// System.out.println(id);

String xpath="//user[@id='"+id+"']";

Node node=dom.selectSingleNode(xpath);

if(node!=null){

// System.out.println("del...");

node.getParent().remove(node);

DomFactory.save();

}

}

}

工具包utils：

获取用户id

package cn.hncu.user.utils;

import java.util.UUID;

public class IDGenerate {

private IDGenerate(){

}

public static String getID(){

// return UUID.randomUUID().toString();

return UUID.randomUUID().toString().replace("-", "");

}

}

对数据库users.xml的dom获取和保存方法

这里用dom4j的包，，，所以要把dom4j两个包导入的相应的位置：

package cn.hncu.user.utils;

import java.io.FileOutputStream;

import org.dom4j.Document;

import org.dom4j.DocumentException;

import org.dom4j.io.SAXReader;

import org.dom4j.io.XMLWriter;

public class DomFactory {

private static Document dom;

private static String fileName;

static{

try {

SAXReader r=new SAXReader();

fileName=DomFactory.class.getClassLoader().getResource("users.xml").getPath();

System.out.println("users.xml的路径:"+fileName);///D:/apache-tomcat-7.0.30/webapps/usersWeb/WEB-INF/classes/users.xml

//注意:获取tomcat中当前项目classpath下的资源方式

dom=r.read(fileName);

} catch (DocumentException e) {

e.printStackTrace();

}

}

public static Document getDom(){

return dom;

}

public static void save(){

XMLWriter w;

try {

w = new XMLWriter(new FileOutputStream(fileName));

w.write(dom);

w.close();

} catch (Exception e) {

e.printStackTrace();

}

}

}

数据库：

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持脚本之家。