Java基础13

Java基础13

Java基础13 1

文件结构 1

Jsp内置对象 2

Jsp测试案例(MyHello.jsp) 4

Jsp+javaBean(java文件)模式开发用户管理系统 4

1. jsp+java_class模式下的用户管理系统模型图 5

2.登录界面_UserManagerSys/src/webRoot/login.jsp 5

3.登录处理界面_UserManagerSys/src/webRoot/loginCl.jsp 6

4.欢迎界面_UserManagerSys/src/webRoot/wel.jsp 7

5.model层_UserManagerSys/src/user.model/UserBeanCl.java 10

6.model层_UserManagerSys/src/user.model/UserBean.java 14

5.model层_UserManagerSys/src/user.model/ConnDB.java 15

登录界面_UserManageSys2/WebRoot/WEB-INF/login.jsp 20

登录处理界面_UserManageSys2/WebRoot/WEB-INF/loginCl.jsp 22

主界面_UserManageSys2/WebRoot/WEB-INF/Main.jsp 24

欢迎界面_UserManageSys2/WebRoot/WEB-INF/wel.jsp 26

修改界面_UserManageSys2/WebRoot/WEB-INF/updateUser.jsp 30

添加用户界面_UserManageSys2/WebRoot/WEB-INF/addUser.jsp 32

操作成功界面_UserManageSys2/WebRoot/WEB-INF/suc.jsp 34

操作失败界面_UserManageSys2/WebRoot/WEB-INF/err.jsp 36

控制器层(controller层) 37

登录处理_UserManageSys2/ src/user.controller/LoginClServer.java 37

处理用户的服务_UserManageSys2/ src/user.controller/UserClServer.java 40

业务逻辑层(model层) 43

Users表_UserManageSys2/src/user.model/UserBean.java 43

表处理_UserManageSys2/ src/user.model/UserBeanCl.java 45

工具类_UserManageSys2/ src/user.model/Tools.java 51

连接数据库_UserManageSys2/ src/user.model/ConnDB.java 52

文件结构

Jsp内置对象

1.out //向客户端输出数据，字节流

out.println("");

2.request //接收客户端的http请求 <----->servlet中的HttpServletRequest

getParameter(String name); //name表表单的参数名

getParameterValues(String name); //得到参数值集，使用String []

setAttribute(String name,Object obj); //设置名字为name的obj,值为obj

getAttribute(String name); //返回由name指定的属性值，如果不存在就返回null;

getCookie();

3.response //封装jsp的产生的回应

addCookie(Cookie cookie);

sendRedirect("./welcome.jsp");

4.session //用于保存用户的信息，跟踪用户的行为

setAttribute(String name,Object obj);

getAttribute(String name);

5.applicattion //多个用户共享该对象，可以做计数器

6.pageContext //代表jsp页面的上下文

7.exception //代表运行的一个异常

getMessage();

8.page //代表jsp这个实例本身(使用比较少)

9.config //代表jsp对应的servlet的配置，可以得到web.xml中的参数

//===========================================================================

//------------session技术--------------

1.得到session

servlet中：HttpSession hs=request.getSession(true);

jsp中：session是一个内置对象，可以直接使用

2.向session添加属性

servlet中：hs.setAttribute(String name,Object val);

jsp中：session.setAttribute(String name,Object o);

3.从session得到某个属性//(getAttribute得到的属性是Object类型，要注意转换类型)

servlet中：hs.getAttribute(String name);

jsp中：session.getAttribute(String name);

4.从session删除掉某个属性

servlet中：hs.removeAttribute(String name);

jsp中：session.removeAttribute(String name);

5.指定session发吊时的存活时间//(这设置成20秒，默认是30分钟)

servlet中：hs.setMaxInactive(20);

jsp中：session.setMaxInactive(20);

6.session的特点：

//1.session是被某个浏览器独占的空间，

//2.当某个浏览器访问网站时，服务器会给浏览器分配一个唯一的session id,以此区分不同客户端

//3.由于session的各个属性要占用服务器内存，因此要迫不得以，才使用，如下情况用：

//1.保存用户信息

//2.保存购物车等

Jsp测试案例(MyHello.jsp)

<%@ page language="java" import="java.util.*" pageEncoding="gb2312"%>

String path = request.getContextPath();

String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">

<html>

<head>

<title>My JSP 'MyHello.jsp' starting page</title>

<!--

-->

</head>

<body>

Hello,维唯为为 <br>

</body>

</html>

Jsp+javaBean(java文件)模式开发用户管理系统

1. jsp+java_class模式下的用户管理系统模型图

2.登录界面_UserManagerSys/src/webRoot/login.jsp

<%@ page language="java" import="java.util.*" pageEncoding="gb2312"%>

String path = request.getContextPath();

String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">

<html>

<head>

<title>My JSP 'login.jsp' starting page</title>

<!--

-->

</head>

用户登录 <br>

<hr>

用户名：<input type="text" name="username"/><br>

密  码：<input type="password" name="passwd"/><br>

</form>

</center>

</body>

</html>

3.登录处理界面_UserManagerSys/src/webRoot/loginCl.jsp

<%@ page language="java" import="java.util.*,java.sql.*,user.model.*" pageEncoding="gb2312"%>

String path = request.getContextPath();

String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">

<html>

<head>

<title>My JSP 'loginCl.jsp' starting page</title>

<!--

-->

</head>

<body>

//接收用户名和密码，完成对用户的验证

String u=request.getParameter("username");

String p=request.getParameter("passwd");

//到数据库中去验证用户

//调用UserBeanCl的方法，完成对用户的验证

UserBeanCl ubc=new UserBeanCl();

if(ubc.checkUser(u,p))

{

response.sendRedirect("wel.jsp?username="+u);

}else

{

response.sendRedirect("login.jsp?errNo=1");

}

</body>

</html>

4.欢迎界面_UserManagerSys/src/webRoot/wel.jsp

<%@ page language="java" import="java.util.*,java.sql.*,user.model.*" pageEncoding="gb2312"%>

String path = request.getContextPath();

String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">

<html>

<head>

<title>My JSP 'wel.jsp' starting page</title>

<!--

-->

</head>

String u=request.getParameter("username");

登录成功！维唯为为恭喜你！<%=u %><br>

<a href="login.jsp">返回重新登录</a>

<hr>

<h1>用户信息列表</h1>

//定义分页用到的变量

int pageNow=1;

//接收用户希望显示的页数(pageNow)

String s_pageNow=request.getParameter("pageNow");

if(s_pageNow!=null)

{

//接收到pageNow

pageNow=Integer.parseInt(s_pageNow);

}

//调用UserBeanCl的方法(创建一个UserBeanCl的实例，然后调用它的某个方法)，完成分布显示

UserBeanCl ubc=new UserBeanCl();

ArrayList al=ubc.getUserByPage(pageNow);

//显示

for(int i=0;i<al.size();i++)

{ //从al中取出UserBean

UserBean ub=(UserBean)al.get(i);

}

</table>

int pageCount=ubc.getPageCount();

int pageSize=ubc.getPageSize();

//首页

out.println("<a href=wel.jsp?pageNow=1&username="+u+">首页</a>");

//上一页

if(pageNow!=1)

{

out.println("<a href=wel.jsp?pageNow="+(pageNow-1)+"&username="+u+">上一页</a>");

}

//显示页面链接

for(int i=pageNow;i<pageNow+pageSize&&i<=pageCount;i++)

{

out.println("<a href=wel.jsp?pageNow="+i+"&username="+u+">["+i+"]</a>");

}

//下一页

if(pageNow!=pageCount)

{

out.println("<a href=wel.jsp?pageNow="+(pageNow+1)+"&username="+u+">下一页</a>");

}

//尾页

out.println("<a href=wel.jsp?pageNow="+pageCount+"&username="+u+">尾页</a>");

</center>

</body>

</html>

5.model层_UserManagerSys/src/user.model/UserBeanCl.java

/**

* 这是一个处理类，有些人把它叫做BO,主要是封装对user表的各种操作，(主要

* 是增，删，修，查...)

package user.model;

import java.sql.*;

import java.util.*;

public class UserBeanCl {

private Statement sm=null;

private ResultSet rs=null;

private Connection ct=null;

private int pageSize=5;

public int getPageSize() {

return pageSize;

}

private int rowCount=0; //行数

private int pageCount=0;//页数

//验证用户是否存在

public boolean checkUser(String u,String p)

{

boolean b=false;

try {

//到数据库去验证

ct=new ConnDB().getConn();

//3.创建Statement

Statement sm=ct.createStatement();

//4.查询

ResultSet rs=sm.executeQuery("select passwd from users where username='"+u+"'");

//验证

if(rs.next())

{

//到此说明输入的用户名存在

if(rs.getString(1).equals(p))

{

b=true;

//合法，跳转wel.jsp

//如何将loginCl.jsp得到的数据传到下一个页面

//1.cookie 2.session 3.response.sendRedirect

//response.sendRedirect("wel.jsp?user="+u);//将用户发送过去

}else

{

//密码错误

}

}else

{

//用户名错误

//不合法，跳转到login.jsp

//response.sendRedirect("login.jsp?errNo=1");

}

} catch (SQLException e) {

e.printStackTrace();

}finally{

//关闭打开的各种资源

this.close();

}

return b;

}

/**

* @author luowei

* @return 返回分页的总页数

public int getPageCount()

{

try {

//得到连接

ct=new ConnDB().getConn();

//3.创建Statement

Statement sm=ct.createStatement();

//4.查询

ResultSet rs=sm.executeQuery("select count(*) from users");

if(rs.next())//将游标从第0条记录移到第1条记录，并判断是否为空

{

rowCount=rs.getInt(1);

}

//计算

if(rowCount%pageSize==0)

{

pageCount=rowCount/pageSize;

}else

{

pageCount=rowCount/pageSize+1;

}

} catch (Exception e) {

e.printStackTrace();

}finally

{

this.close();

}

return pageCount;

}

/**@得到用户需要显示的用户信息(分页)

* @author luowei

* @param pageNow:当前页

* @return

public ArrayList getUserByPage(int pageNow)

{

ArrayList al=new ArrayList();

try {

//得到连接

ct=new ConnDB().getConn();

//3.创建Statement

Statement sm=ct.createStatement();

//查询出需要显示的记录

rs=sm.executeQuery("select * from users limit "+(pageSize*(pageNow-1))+","+pageSize);

//开始将rs封装到ArrayList

while(rs.next())

{

UserBean ub=new UserBean();

ub.setUserId(rs.getInt(1));

ub.setUsername(rs.getString(2));

ub.setPasswd(rs.getString(3));

ub.setEmail(rs.getString(4));

ub.setGrade(rs.getInt(5));

al.add(ub);

}

} catch (Exception e) {

e.printStackTrace();

}finally{

this.close();

}

return al;

}

/**@author luowei

* @see关闭资源

* @return null

public void close()

{

try {

if(rs!=null)

{

rs.close();

rs=null;

}

if(sm!=null)

{

sm.close();

sm=null;

}

if(ct!=null)

{

ct.close();

ct=null;

}

} catch (Exception e) {

e.printStackTrace();

}

6.model层_UserManagerSys/src/user.model/UserBean.java

/**

* 这是一个javabean,对应user表，代表数据

* 他的一个实例(对象),对应users的一条

package user.model;

public class UserBean {

public int getUserId() {

return userId;

}

public void setUserId(int userId) {

this.userId = userId;

}

public String getUsername() {

return username;

}

public void setUsername(String username) {

this.username = username;

}

public String getPasswd() {

return passwd;

}

public void setPasswd(String passwd) {

this.passwd = passwd;

}

public String getEmail() {

return email;

}

public void setEmail(String email) {

this.email = email;

}

public int getGrade() {

return grade;

}

public void setGrade(int grade) {

this.grade = grade;

}

private int userId;

private String username;

private String passwd;

private String email;

private int grade;

}

5.model层_UserManagerSys/src/user.model/ConnDB.java

/**

* 得到数据库的连接

package user.model;

import java.sql.*;

public class ConnDB {

private Connection ct=null;

public Connection getConn()

{

try {

//1.加载驱动

Class.forName("org.gjt.mm.mysql.Driver").newInstance();

//Class.forName("com.microsoft.jdbc.sqlserver.SQLServerDriver").newInstance();

//2.得到连接

ct=DriverManager.getConnection("jdbc:mysql://localhost:3306/test_user","root","root");

//ct=DriverManager.getConnection("jdbc:microsoft:sqlserver://localhost:1433;databaseName=testusr","sa","luowei");

} catch (Exception e) {

e.printStackTrace();

}

return ct;

}

MVC模式开发用户管理系统

1. MVC模介绍

MVC模型图

mvc用户管理系统模型图

2.向数据库添加用户表

create database test_user;

use test_user;

create table users(

useId int primary key AUTO_INCREMENT,#用户id号

username varchar(20),

passwd varchar(20),

email varchar(30),

grade int #用户的级别

);

insert into users values(null,"admin","admin","admin@sohu.com","1");

insert into users values(null,"luowei","luowei505050","luowei@163.com","1");

insert into users values(null,"test1","test1","test1@sina.com","5");

insert into users values(null,"test2","test2","test2@sina.com","2");

insert into users values(null,"test3","test3","test3@sina.com","5");

insert into users values(null,"test4","test4","test4@sina.com","6");

insert into users values(null,"test5","test5","test5@sina.com","6");

insert into users values(null,"test6","test6","test6@sina.com","7");

insert into users values(null,"test7","test7","test7@sina.com","7");

insert into users values(null,"test8","test8","test8@sina.com","8");

insert into users values(null,"test9","test9","test9@sina.com","8");

insert into users values(null,"test10","test10","test10@sina.com","9");

insert into users values(null,"test11","test11","test11@sina.com","3");

insert into users values(null,"test12","test12","test12@sina.com","4");

select * from users;

insert into users(username,passwd,email,grade) select username,passwd,email,grade from users;

select * from users where username=admin and passwd=admin;

#添加新列

alter table users add myPic varchar(30);

#修改数据

update users set myPic='luowei.gif' where userName='luowei';

update users set myPic='admin.gif' where userName='admin';

update users set myPic='test1.gif' where userName='test1';

#drop table users;

#--------------------------------------------------------------------

CREATE TABLE person (

id SMALLINT UNSIGNED NOT NULL AUTO_INCREMENT,

name CHAR(60) NOT NULL,

PRIMARY KEY (id)

);

CREATE TABLE shirt (

id SMALLINT UNSIGNED NOT NULL AUTO_INCREMENT,

style ENUM('t-shirt', 'polo', 'dress') NOT NULL,

color ENUM('red', 'blue', 'orange', 'white', 'black') NOT NULL,

owner SMALLINT UNSIGNED NOT NULL REFERENCES person(id),

PRIMARY KEY (id)

);

INSERT INTO person VALUES (NULL, 'Antonio Paz');

SELECT @last := LAST_INSERT_ID();

INSERT INTO shirt VALUES

(NULL, 'polo', 'blue', @last),

(NULL, 'dress', 'white', @last),

(NULL, 't-shirt', 'blue', @last);

INSERT INTO person VALUES (NULL, 'Lilliana Angelovska');

SELECT @last := LAST_INSERT_ID();

INSERT INTO shirt VALUES

(NULL, 'dress', 'orange', @last),

(NULL, 'polo', 'red', @last),

(NULL, 'dress', 'blue', @last),

(NULL, 't-shirt', 'white', @last);

SELECT * FROM person;

SELECT * FROM shirt;

SELECT s.* FROM person p, shirt s

WHERE p.name LIKE 'Lilliana%'

AND s.owner = p.id

AND s.color <> 'white';

#----------------------------------------------------------

select * from users order by useId limit 5;

界面层(View层)

登录界面_UserManageSys2/WebRoot/WEB-INF/login.jsp

<%@ page language="java" import="java.util.*" pageEncoding="gb2312"%>

String path = request.getContextPath();

String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">

<html>

<head>

<title>My JSP 'login.jsp' starting page</title>

<!--

-->

</head>

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

if(errNo!=null)

{

if(errNo.equals("1"))

{

out.println("<font color=red size=7>登录错误，请输入正确的用户名和密码！</font><br>");

}

<hr>

用户登录 <br>

用户名：<input type="text" name="username"/><br>

密  码：<input type="password" name="passwd"/><br>

</form>

<hr>

</center>

</body>

</html>

登录处理界面_UserManageSys2/WebRoot/WEB-INF/loginCl.jsp

<%@ page language="java" import="java.util.*,java.sql.*,user.model.*" pageEncoding="gb2312"%>

String path = request.getContextPath();

String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">

<html>

<head>

<title>My JSP 'loginCl.jsp' starting page</title>

<!--

-->

</head>

<body>

//接收用户名和密码，完成对用户的验证

String u=request.getParameter("username");

String p=request.getParameter("passwd");

//到数据库中去验证用户

//调用UserBeanCl的方法，完成对用户的验证

UserBeanCl ubc=new UserBeanCl();

if(ubc.checkUser(u,p))

{

response.sendRedirect("wel.jsp?username="+u);

}else

{

response.sendRedirect("login.jsp?errNo=1");

}

</body>

</html>

主界面_UserManageSys2/WebRoot/WEB-INF/Main.jsp

<%@ page language="java" import="java.util.*" pageEncoding="gb2312"%>

String path = request.getContextPath();

String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">

<html>

<head>

<title>My JSP 'Main.jsp' starting page</title>

<!--

-->

</head>

String u=request.getParameter("username");

//System.out.println("Main.jsp得到的username="+u);

<hr>

<h1>请选择操作</h1>

<hr>

</center>

</body>

</html>

欢迎界面_UserManageSys2/WebRoot/WEB-INF/wel.jsp

<%@ page language="java" import="java.util.*,java.sql.*,user.model.*" pageEncoding="gb2312"%>

String path = request.getContextPath();

String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">

<html>

<head>

<title>My JSP 'wel.jsp' starting page</title>

<!--

-->

<!--

function msg()

{

return window.confirm("你确认要删除吗？");

}

-->

</script>

</head>

String u=request.getParameter("username");

//System.out.println("UserClServlet得到的username="+u);

//u=new String(u.getBytes("gb2312"),"iso-8859-1"); //转码

//防止用户非法登录

String userName=(String)session.getAttribute("myName");

//如果用户没有登录

if(userName==null)

{

//返回登录界面

response.sendRedirect("login.jsp?errNo=1");

return ;

}

登录成功！维唯为为恭喜你！<%=u %><br/>

session得到的用户名为：<%=userName %><br/>

<a href="login.jsp">返回重新登录</a>  

<a href="Main.jsp?username=<%=u %>">返回主界面</a>

<hr>

<h1>用户信息列表</h1>

//调用UserBeanCl的方法(创建一个UserBeanCl的实例，然后调用它的某个方法)，完成分布显示

//UserBeanCl ubc=new UserBeanCl();

//ArrayList al=ubc.getUserByPage(pageNow);

//要显示的用户信息从request中取

ArrayList al=(ArrayList)request.getAttribute("result");

//显示

//得到pageCount

String s_pageCount=(String)request.getAttribute("pageCount");

int pageCount=Integer.parseInt(s_pageCount);

String s_pageSize=(String)request.getAttribute("pageSize");

int pageSize=Integer.parseInt(s_pageSize);

String s_pageNow=(String)request.getAttribute("pageNow");

int pageNow=Integer.parseInt(s_pageNow);

//定义一个颜色数组

String []color={"silver","pink"};

for(int i=0;i<al.size();i++)

{ //从al中取出UserBean

UserBean ub=(UserBean)al.get(i);

<td><a href="updateUser.jsp?username=<%=u%>&pageNow=<%=pageNow %>&userId=<%=ub.getUserId()

%>&userName=<%=ub.getUsername() %>&passWd=<%=ub.getPasswd() %>&email=<%=ub.getEmail()

%>&grade=<%=ub.getGrade() %>">修改用户</a></td>

<td><a onclick="return msg()" href="UserClServlet?username=<%=u%>&pageNow=<%=pageNow

%>&flag=delUser&userid=<%=ub.getUserId() %>">删除用户</a></td></tr>

}

</table>

//首页

out.println("<a href=UserClServlet?flag=fenye&pageNow=1&username="+u+">首页</a>"); //转到分页控制器处理

//上一页

if(pageNow!=1)

{

out.println("<a href=UserClServlet?flag=fenye&pageNow="+(pageNow-1)+"&username="+u+">上一页</a>");

}

//显示页面链接

for(int i=pageNow;i<pageNow+pageSize&&i<=pageCount;i++)

{

out.println("<a href=UserClServlet?flag=fenye&pageNow="+i+"&username="+u+">["+i+"]</a>");

}

//下一页

if(pageNow!=pageCount)

{

out.println("<a href=UserClServlet?flag=fenye&pageNow="+(pageNow+1)+"&username="+u+">下一页</a>");

}

//尾页

out.println("<a href=UserClServlet?flag=fenye&pageNow="+pageCount+"&username="+u+">尾页</a>");

<hr>

</center>

</body>

</html>

修改界面_UserManageSys2/WebRoot/WEB-INF/updateUser.jsp

<%@ page language="java" import="java.util.*" pageEncoding="gb2312"%>

String path = request.getContextPath();

String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">

<html>

<head>

<title>My JSP 'updateUser.jsp' starting page</title>

<!--

-->

</head>

String u=request.getParameter("username");

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

//String flag=request.getParameter("flag");

//System.out.println("Main.jsp得到的username="+u);

欢迎您：<%=u %><br>

<a href="Main.jsp?username=<%=u %>">返回主界面</a>

<a href="UserClServlet?username=<%=u %>&UserClServlet=<%=u %>&pageNow=<%=pageNow %>&flag=fenye">返回上一页</a>

<hr>

<h1>修改用户信息</h1>

<form action="UserClServlet?pageNow=1&flag=updateUser&username=<%=u %>" method="post">

</table>

</form>

<hr>

</center>

</body>

</html>

添加用户界面_UserManageSys2/WebRoot/WEB-INF/addUser.jsp

<%@ page language="java" import="java.util.*" pageEncoding="gb2312"%>

String path = request.getContextPath();

String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">

<html>

<head>

<title>My JSP 'addUser.jsp' starting page</title>

<!--

-->

</head>

String u=request.getParameter("username");

//System.out.println("Main.jsp得到的username="+u);

欢迎您：<%=u %><br>

<a href="Main.jsp?username=<%=u %>">返回主界面</a>

<hr>

<h1>请输入用户信息</h1>

<form action="UserClServlet?pageNow=1&flag=addUser&username=<%=u %>" method="post">

</table>

</form>

<hr>

</center>

</body>

</html>

操作成功界面_UserManageSys2/WebRoot/WEB-INF/suc.jsp

<%@ page language="java" import="java.util.*" pageEncoding="gb2312"%>

String path = request.getContextPath();

String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">

<html>

<head>

<title>My JSP 'login.jsp' starting page</title>

<!--

-->

</head>

<hr>

String u=request.getParameter("username");

//String pageNow=request.getParameter("pageNow");

//String flag=request.getParameter("flag");

<a href="Main.jsp?username=<%=u %>">返回主界面</a>

<!--

<a href="addUser.jsp?username=<%=u %>">返回上一页</a>

-->

<hr>

</center>

</body>

</html>

操作失败界面_UserManageSys2/WebRoot/WEB-INF/err.jsp

<%@ page language="java" import="java.util.*" pageEncoding="gb2312"%>

String path = request.getContextPath();

String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">

<html>

<head>

<title>My JSP 'login.jsp' starting page</title>

<!--

-->

</head>

<hr>

String u=request.getParameter("username");

//String pageNow=request.getParameter("pageNow");

//String flag=request.getParameter("flag");

<h1>操作不成功！</h1><br>

<a href="Main.jsp?username=<%=u %>">返回主界面</a>

<!--

<a href="addUser.jsp?username=<%=u %>">返回上一页</a>

-->

<hr>

</center>

</body>

</html>

控制器层(controller层)

登录处理_UserManageSys2/ src/user.controller/LoginClServer.java

/**

* 这是一个控制器，主要完成对用户身份的验证

* 控制器本身是不会去完成业务逻辑，它主要是去调用模型完成对数据的处理

package user.controller;

import user.model.*;

import java.io.IOException;

import java.io.PrintWriter;

import java.util.*;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

public class LoginClServlet extends HttpServlet {

/**

* The doGet method of the servlet. <br>

* This method is called when a form has its tag value method equals to get.

* @param request the request send by the client to the server

* @param response the response send by the server to the client

* @throws ServletException if an error occurred

* @throws IOException if an error occurred

public void doGet(HttpServletRequest request, HttpServletResponse response)

throws ServletException, IOException {

//得到用户名和密码

String u=request.getParameter("username");

//u=new String(u.getBytes("iso-8859-1"),"gb2312");//将用户名转码，解决中文乱码而导致的验证错误

String p=request.getParameter("passwd");

System.out.println("username="+u+" password="+p);

//使用模型(UserBeanCl)，完成对用户的验证

//1.创建一个UserBeanCl对象

UserBeanCl ubc=new UserBeanCl();

//调用方法

if(ubc.checkUser(u, p))

{

//System.out.println("使用了servlet控制器完成验证！");

//在跳转到wel.jsp页面时，就把要显示的数据给wel.jsp准备好

ArrayList al=ubc.getUserByPage(1);

int pageCount=ubc.getPageCount();

int pageSize=ubc.getPageSize();

//将al,pageCount,pageNow,pageSize放入request当中

request.setAttribute("result", al);

request.setAttribute("pageCount", pageCount+"");

//因为第二个参数是对象，用int直接传递，后边使用时不好处理，所以把它转成String

request.setAttribute("pageSize", pageSize+"");

request.setAttribute("pageNow", "1");

//合法

//response.sendRedirect("wel.jsp?username="+u);

//因为sendRedirect方法效率不高，所以一般多是用转发的方法

//将用户名放入session,以备后用

request.getSession().setAttribute("myName", u);

//这种方法的效率高，同时保证了request中的原有对象还可以在下一面页使用

//所以就不需要加(?username="+u)了

request.getRequestDispatcher("Main.jsp").forward(request, response);

}else

{

//不合法

request.getRequestDispatcher("login.jsp").forward(request, response);

System.out.println("LoginClServlet验证不合法");

}

/**

* The doPost method of the servlet. <br>

* This method is called when a form has its tag value method equals to post.

* @param request the request send by the client to the server

* @param response the response send by the server to the client

* @throws ServletException if an error occurred

* @throws IOException if an error occurred

public void doPost(HttpServletRequest request, HttpServletResponse response)

throws ServletException, IOException {

//合二为一

this.doGet(request, response);

}

处理用户的服务_UserManageSys2/ src/user.controller/UserClServer.java

/**

* 这个控制器，将处理用户的分页显示，用户的删除，修改，添加

package user.controller;

import java.io.IOException;

import java.io.PrintWriter;

import java.util.ArrayList;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import user.model.*;

public class UserClServlet extends HttpServlet {

/**

* The doGet method of the servlet. <br>

* This method is called when a form has its tag value method equals to get.

* @param request the request send by the client to the server

* @param response the response send by the server to the client

* @throws ServletException if an error occurred

* @throws IOException if an error occurred

public void doGet(HttpServletRequest request, HttpServletResponse response)

throws ServletException, IOException {

//获得标志

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

if(flag.equals("fenye")) //如果是分页

{

try {

//得到用户希望显示的信息

int pageNow=Integer.parseInt(request.getParameter("pageNow"));

String u=request.getParameter("username");

System.out.println("UserClServlet得到的username="+u);

//调用UserBeanCl

UserBeanCl ubc=new UserBeanCl();

//在跳转到wel.jsp页面时，就把要显示的数据给wel.jsp准备好

ArrayList al=ubc.getUserByPage(pageNow); //经UserBeanCl处理后，获得当前页的数据

int pageCount=ubc.getPageCount();

int pageSize=ubc.getPageSize();

//将al,pageCount,pageNow,pageSize放入request当中

request.setAttribute("result", al);

request.setAttribute("pageCount", pageCount+"");

//因为第二个参数是对象，用int直接传递，后边使用时不好处理，所以把它转成String

request.setAttribute("pageSize", pageSize+"");

request.setAttribute("username", u);

request.setAttribute("pageNow", pageNow+"");

//重新跳转回wel.jsp

request.getRequestDispatcher("wel.jsp").forward(request, response);

} catch (Exception e) {

e.printStackTrace();

}

}else if(flag.equals("delUser")) //如果是删除

{

//完成删除

//1.得到要删除的用户的id

String userId=request.getParameter("userid");

//创建UserBeanCl

UserBeanCl ubc=new UserBeanCl();

if(ubc.delUserById(userId))

{

//删除成功

request.getRequestDispatcher("suc.jsp").forward(request, response);

}else

{

//删除失败

request.getRequestDispatcher("err.jsp").forward(request, response);

}

}else if(flag.equals("addUser")) //如果是添加

{

//完成添加用户

//1.得到用户输入的信息

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

String passwd=request.getParameter("password");

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

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

//创建UserBeanCl

UserBeanCl ubc=new UserBeanCl();

if(ubc.addUser(name, passwd, email, grade))

{

//添加成功

request.getRequestDispatcher("suc.jsp").forward(request, response);

}else

{

//添加失败

request.getRequestDispatcher("err.jsp").forward(request, response);

}

}else if(flag.equals("updateUser")) //如果是修改

{

//完成添加用户

//1.得到用户输入的信息

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

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

String passwd=request.getParameter("passWd");

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

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

//创建UserBeanCl

UserBeanCl ubc=new UserBeanCl();

if(ubc.updateUser(id,name, passwd, email, grade))

{

//修改成功

request.getRequestDispatcher("suc.jsp").forward(request, response);

}else

{

//修改失败

request.getRequestDispatcher("err.jsp").forward(request, response);

}

/**

* The doPost method of the servlet. <br>

* This method is called when a form has its tag value method equals to post.

* @param request the request send by the client to the server

* @param response the response send by the server to the client

* @throws ServletException if an error occurred

* @throws IOException if an error occurred

public void doPost(HttpServletRequest request, HttpServletResponse response)

throws ServletException, IOException {

this.doGet(request, response);

}

业务逻辑层(model层)

Users表_UserManageSys2/src/user.model/UserBean.java

/**

* 这是一个javabean,对应user表，代表数据

* 他的一个实例(对象),对应users的一条

package user.model;

public class UserBean {

public int getUserId() {

return userId;

}

public void setUserId(int userId) {

this.userId = userId;

}

public String getUsername() {

return username;

}

public void setUsername(String username) {

this.username = username;

}

public String getPasswd() {

return passwd;

}

public void setPasswd(String passwd) {

this.passwd = passwd;

}

public String getEmail() {

return email;

}

public void setEmail(String email) {

this.email = email;

}

public int getGrade() {

return grade;

}

public void setGrade(int grade) {

this.grade = grade;

}

private int userId;

private String username;

private String passwd;

private String email;

private int grade;

}

表处理_UserManageSys2/ src/user.model/UserBeanCl.java

/**

* 这是一个处理类，有些人把它叫做BO,主要是封装对user表的各种操作，(主要

* 是增，删，修，查...)

package user.model;

import java.io.UnsupportedEncodingException;

import java.sql.*;

import java.util.*;

public class UserBeanCl {

private Statement sm=null;

private ResultSet rs=null;

private Connection ct=null;

private int pageSize=5;

public int getPageSize() {

return pageSize;

}

private int rowCount=0; //行数

private int pageCount=0;//页数

/**

* 验证用户是否存在

* @param u

* @param p

* @return

public boolean checkUser(String u,String p)

{

boolean b=false;

try {

//到数据库去验证

ct=new ConnDB().getConn();

//3.创建Statement

Statement sm=ct.createStatement();

//4.查询

ResultSet rs=sm.executeQuery("select passwd from users where username='"+u+"'");

//验证

if(rs.next())

{

//到此说明输入的用户名存在

if(rs.getString(1).equals(p))

{

b=true;

//合法，跳转wel.jsp

//如何将loginCl.jsp得到的数据传到下一个页面

//1.cookie 2.session 3.response.sendRedirect

//response.sendRedirect("wel.jsp?user="+u);//将用户发送过去

}else

{

//密码错误

}

}else

{

//用户名错误

//不合法，跳转到login.jsp

//response.sendRedirect("login.jsp?errNo=1");

}

} catch (SQLException e) {

e.printStackTrace();

}finally{

//关闭打开的各种资源

this.close();

}

return b;

}

/**添加用户

* @author luowei

* @param name:用户名

* @param passwd:密码

* @param email:电子邮件

* @param grade:级别

* @return boolean

public boolean addUser(String name,String passwd,String email,String grade)

{

boolean b=false;

try {

//得到连接

ct=new ConnDB().getConn();

sm=ct.createStatement();

//执行

int a=sm.executeUpdate("insert into users(username,passwd,email,grade) "

+"values('"+name+"','"+passwd+"','"+email+"','"+grade+"') ");

if(a==1) //1表示是否是成功的添加了1条记录

{

//添加成功

b=true;

}

} catch (Exception e) {

e.printStackTrace();

}

return b;

}

/**

* 修改用户

* @author luowei

public boolean updateUser(String id,String name,String passwd,String email,String grade)

{

boolean b=false;

try {

//得到连接

ct=new ConnDB().getConn();

sm=ct.createStatement();

//执行

int a=sm.executeUpdate("update users set username='"+name+"',passwd='"+passwd+"',email='"

+email+"',grade='"+grade+"' where useId='"+id+"'");

if(a==1) //1表示是否是成功的修改了1条记录

{

//修改成功

b=true;

}

} catch (Exception e) {

e.printStackTrace();

}

return b;

}

/**删除用户

* @author luowei

public boolean delUserById(String id)

{

boolean b=false;

//int Id=Integer.parseInt(id);

try {

//得到连接

ct=new ConnDB().getConn();

sm=ct.createStatement();

//执行

int a=sm.executeUpdate("delete from users where useId='"+id+"'");

if(a==1)

{

//删除成功

b=true;

}

} catch (Exception e) {

e.printStackTrace();

}finally{

this.close();

}

return b;

}

/**

* @author luowei

* @return 返回分页的总页数

public int getPageCount()

{

try {

//得到连接

ct=new ConnDB().getConn();

//3.创建Statement

Statement sm=ct.createStatement();

//4.查询

ResultSet rs=sm.executeQuery("select count(*) from users");

if(rs.next())//将游标从第0条记录移到第1条记录，并判断是否为空

{

rowCount=rs.getInt(1);

}

//计算

if(rowCount%pageSize==0)

{

pageCount=rowCount/pageSize;

}else

{

pageCount=rowCount/pageSize+1;

}

} catch (Exception e) {

e.printStackTrace();

}finally

{

this.close();

}

return pageCount;

}

/**得到用户需要显示的用户信息(分页)

* @author luowei

* @param 当前页

* @return

public ArrayList getUserByPage(int pageNow)

{

ArrayList al=new ArrayList();

try {

//得到连接

ct=new ConnDB().getConn();

//3.创建Statement

Statement sm=ct.createStatement();

//查询出需要显示的记录

rs=sm.executeQuery("select * from users order by useId limit "+(pageSize*(pageNow-1))+","+pageSize);

//开始将rs封装到ArrayList

while(rs.next())

{

UserBean ub=new UserBean();

ub.setUserId(rs.getInt(1));

ub.setUsername(rs.getString(2));

ub.setPasswd(rs.getString(3));

ub.setEmail(rs.getString(4));

ub.setGrade(rs.getInt(5));

al.add(ub);

}

} catch (Exception e) {

e.printStackTrace();

}finally{

this.close();

}

return al;

}

/**@author luowei

* @see关闭资源

* @return null

public void close()

{

try {

if(rs!=null)

{

rs.close();

rs=null;

}

if(sm!=null)

{

sm.close();

sm=null;

}

if(ct!=null)

{

ct.close();

ct=null;

}

} catch (Exception e) {

e.printStackTrace();

}

工具类_UserManageSys2/ src/user.model/Tools.java

/**

* 工具类

package user.model;

public class Tools {

/**提供一个方法，将乱码转成gb2312,gbk,utf-8

* @param input

* @return

public static String getNewString(String input)

{

String result="";

try{

result=new String(input.getBytes("gb2312"),"iso-8859-1");

}catch(Exception e)

{

e.printStackTrace();

}

return result;

}

连接数据库_UserManageSys2/ src/user.model/ConnDB.java

/**

* 得到数据库的连接

package user.model;

import java.sql.*;

public class ConnDB {

private Connection ct=null;

public Connection getConn()

{

try {

//1.加载驱动

Class.forName("org.gjt.mm.mysql.Driver").newInstance();

//Class.forName("com.microsoft.jdbc.sqlserver.SQLServerDriver").newInstance();

//2.得到连接

ct=DriverManager.getConnection("jdbc:mysql://localhost:3306/test_user","root","root");

//ct=DriverManager.getConnection("jdbc:microsoft:sqlserver://localhost:1433;databaseName=testusr","sa","luowei");

} catch (Exception e) {

e.printStackTrace();

}

return ct;

}