java se开发web-USB迷|专注于互联网分享

java se开发web

准备工作：

1.在WebContent WEB-INF lib下添加c3p0-0.9.5.2.jar mchange-common-java-0.2.11.jar ojdbc6.jar

2.java Resources中的src平级的添加c3p0-config.xml

Java Resources

src

三个包

com.hanqi.dao 　　　　　　数据库有关

BankCard.java实体类　　属性 getter setter toString 有参构造无参构造

BankCardDAO.java　　　功能类数据库增删改查

DBHelper.java　　　　　　单例的数据库工具类返回数据连接连接池

com.hanqi.service

BankCardService.java　　业务逻辑类

com.hanqi.web

CheckLoginServlet.java

MyFilter.java　　　　　　　　过滤器

WebContent

Main.jsp 主页面

Insert title here卡号：
密码：

CheckLoginServlet.java

package com.hanqi.web;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import javax.servlet.http.HttpSession;

import com.hanqi.dao.BankCard;

import com.hanqi.service.BankCardService;/**

* Servlet implementation class CheckLoginServlet*/

public classCheckLoginServlet extends HttpServlet {private static final long serialVersionUID = 1L;/**

* @see HttpServlet#HttpServlet()*/

publicCheckLoginServlet() {

super();//TODO Auto-generated constructor stub

}/**

* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)*/

protected voiddoGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {//接收参数

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

String password= request.getParameter("password");//对get,post同时有效//cardid = new String(cardid.getBytes("ISO-8859-1"), "UTF-8");//检查参数

if (cardid == null || password == null

|| cardid.trim().equals("")|| password.trim().equals(""))

{

response.getWriter().println("请正确登录");

response.setHeader("refresh", "3;url=Login.jsp");

}else{//验证参数//调用Service层

BankCard bc = newBankCardService().checkLogin(cardid, password);if (bc != null)

{//创建session

HttpSession hs =request.getSession();

hs.setAttribute("bankcard", bc);//跳转

response.sendRedirect("Main.jsp");

}else{

response.getWriter().println("卡号或密码错误" + "cardid =" +cardid);

response.setHeader("refresh", "3;url=Login.jsp");

}

}/**

* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)*/

protected voiddoPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {//TODO Auto-generated method stub

doGet(request, response);

}

BankCard.java

package com.hanqi.dao;

import java.util.Date;//实体类

public classBankCard {privateString cardID;privateString userID;privateString userName;privateString password;private doublebalance;privateString state;privateDate createTime;publicString getCardID() {returncardID;

}public voidsetCardID(String cardID) {this.cardID =cardID;

}publicString getUserID() {returnuserID;

}public voidsetUserID(String userID) {this.userID =userID;

}publicString getUserName() {returnuserName;

}public voidsetUserName(String userName) {this.userName =userName;

}publicString getPassword() {returnpassword;

}public voidsetPassword(String password) {this.password =password;

}public doublegetBalance() {returnbalance;

}public void setBalance(doublebalance) {this.balance =balance;

}publicString getState() {returnstate;

}public voidsetState(String state) {this.state =state;

}publicDate getCreateTime() {returncreateTime;

}public voidsetCreateTime(Date createTime) {this.createTime =createTime;

}publicBankCard(String userID, String userName, String password) {

super();this.userID =userID;this.userName =userName;this.password =password;

}publicBankCard() {

super();

}

@OverridepublicString toString() {return "BankCard [cardID=" + cardID + ", userID=" + userID + ", userName=" + userName + ", password=" +password+ ", balance=" + balance + ", state=" + state + ", createTime=" + createTime + "]";

}

BankCardDAO.java

package com.hanqi.dao;

import java.sql.Connection;

import java.sql.PreparedStatement;

import java.sql.ResultSet;

import java.sql.SQLException;//数据库操作类

public classBankCardDAO {//查//单条查询

publicBankCard getBankCard(String cardid)

{

BankCard rtn= null;//查询

Connection conn = null;

PreparedStatement ps= null;

ResultSet rs= null;try{

conn=DBHelper.getDBHelper().getConnection();

String sql= "select * from t_bankcard where card_id = ?";

ps=conn.prepareStatement(sql);

ps.setString(1, cardid);

rs=ps.executeQuery();if(rs.next())

{

rtn= newBankCard();

rtn.setCardID(cardid);

rtn.setBalance(rs.getDouble("Balance"));

rtn.setCreateTime(rs.getDate("create_time"));

rtn.setPassword(rs.getString("password"));

rtn.setState(rs.getString("state"));

rtn.setUserID(rs.getString("user_id"));

rtn.setUserName(rs.getString("user_name"));

}

}catch(SQLException e) {

e.printStackTrace();

}finally{try{

rs.close();

}catch(SQLException e2) {

}try{

ps.close();

}catch(SQLException e1) {

}try{

conn.close();

}catch(SQLException e) {

}

}returnrtn;

}//增//改//删

}

DBHelper.java

package com.hanqi.dao;

import java.sql.Connection;

import java.sql.SQLException;

import com.mchange.v2.c3p0.ComboPooledDataSource;//单例模式的数据库工具类//返回数据库连接

public classDBHelper {//1 隐藏默认构造方法

privateDBHelper()

{

}//2 静态实例

private staticDBHelper dh;//3 返回实例的静态方法

public staticDBHelper getDBHelper()

{if (dh == null)

{

dh= newDBHelper();

}returndh;

}private ComboPooledDataSource cpds = new ComboPooledDataSource("helloc3p0");//返回连接的方法

publicConnection getConnection() throws SQLException

{returncpds.getConnection();

}

MyFilter.java

package com.hanqi.web;

import java.io.IOException;

import javax.servlet.Filter;

import javax.servlet.FilterChain;

import javax.servlet.FilterConfig;

import javax.servlet.ServletException;

import javax.servlet.ServletRequest;

import javax.servlet.ServletResponse;/**

* Servlet Filter implementation class MyFilter*/

public classMyFilter implements Filter {/**

* Default constructor.*/

publicMyFilter() {//TODO Auto-generated constructor stub

}/**

* @see Filter#destroy()*/

public voiddestroy() {//TODO Auto-generated method stub

}/**

* @see Filter#doFilter(ServletRequest, ServletResponse, FilterChain)*/

public voiddoFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {//设置编码

request.setCharacterEncoding("UTF-8");

response.setContentType("text/html");

response.setCharacterEncoding("UTF-8");

chain.doFilter(request, response);

}/**

* @see Filter#init(FilterConfig)*/

public voidinit(FilterConfig fConfig) throws ServletException {//TODO Auto-generated method stub

}

BankCardService.java

package com.hanqi.service;

import com.hanqi.dao.BankCard;

import com.hanqi.dao.BankCardDAO;//业务逻辑类

public classBankCardService {//验证登录方法

publicBankCard checkLogin(String cardid, String password)

{

BankCard rtn= null;//得到卡信息

BankCard bc = newBankCardDAO().getBankCard(cardid);if (bc != null)

{//验证数据有效性

if (bc.getState().equals("1")&&bc.getPassword().equals(password))

{

rtn=bc;

}

}returnrtn;

}

Main.jsp

Insert title here

{out.print("会话超时或未登录");

response.setHeader("refresh", "3;url=Login.jsp");

}else{

BankCard bc=(BankCard)obj;out.print("欢迎登录！" +bc.getUserName());

}%>