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//reg.java
//import required classes
import java.sql.*;
public class reg
{
public int newID = 0;
public boolean result = false;
public boolean reg(String username,String password,String confirm,String email)
{
try{
if(!this.checkUser(username))
return false;
if(!this.checkPwd(password))
return false;
if(!this.verifyPwd(password,confirm))
return false;
if(!this.checkEmail(email))
return false;
if(!this.userNotExit(username))
return false;
this.getNewID();
this.result = this.register(username,password,confirm,email);
return this.result;
}catch(Exception e){
System.out.println(e.toString());
return false;
}
}//End boolean reg
public boolean checkUser(String user)
{
try{
if(user.indexOf("'")!=-1)
{
System.out.println("姓名中含有非法字符！");
return false;
}else
return true;
}catch(Exception e){
System.out.println(e.toString());
return false;
}
}
public boolean checkPwd(String pwd)
{
try{
if(pwd.indexOf("'")!=-1)
{
System.out.println("密码中含有非法字符！");
return false;
}else
return true;
}catch(Exception e){
System.out.println(e.toString());
return false;
}
}
public boolean verifyPwd(String pwd,String confirm)
{
try{
if(!pwd.equals(confirm))
{
System.out.println("两次输入的密码不一致！");
return false;
}else
return true;
}catch(Exception e){
System.out.println(e.toString());
return false;
}
}
public boolean checkEmail(String email)
{
try{
if(email.indexOf("'")!=-1)
{
System.out.println("E-mail中含有非法字符！");
return false;
}else
return true;
}catch(Exception e){
System.out.println(e.toString());
return false;
}
}
public boolean userNotExit(String user)
{
try{
DBConn userDBConn = new DBConn();
userDBConn.executeQuery("select * from tbl_user where name='" + user + "'");
if(userDBConn.rs_next())
{
System.out.println("用户名已存在，请选择其它的用户名！");
return false;
}else
return true;
}catch(Exception e){
System.out.println(e.toString());
return false;
}
}
public int getNewID()
{
try{
DBConn newIDDBConn = new DBConn();
newIDDBConn.executeQuery("select * from tbl_user order by id desc limit 1");
if(newIDDBConn.rs_next())
{
this.newID = newIDDBConn.rs_getInt("id") + 1;
System.out.println(this.newID);
}else{
this.newID = 1;
}
return this.newID;
}catch(Exception e){
System.out.println(e.toString());
return -1;
}
}
public int getID()
{
return this.newID;
}
public boolean register(String username,String password,String confirm,String email)
{
try{
DBConn regDBConn = new DBConn();
String strSQL = "insert into tbl_user(id,name,pwd,email) values('" + this.newID +"','" + username + "','" + password + "','" + email + "')";
regDBConn.execute(strSQL);
return true;
}catch(Exception e){
System.out.println(e.toString());
return false;
}
}
public static void main(String args[])
{
try{
reg newreg = new reg();
System.out.println(newreg.reg("sssssssss","ssssss","ssssss","imagebear@163.com"));
DBConn myconn = new DBConn();
myconn.executeQuery("select * from tbl_user");
while(myconn.rs_next())
{
System.out.println(myconn.rs_getInt("id") + " " + myconn.rs_getString("name") + " " + myconn.rs_getString("pwd") + " " + myconn.rs_getString("email"));
}
System.out.println(newreg.getID());
}catch(Exception e){
System.err.println(e.toString());
}
}
};
说明：
1、该bean文件应和上文所述DBConn.class文件放于同一目录下
2、本例主要研究注册的过程，其中的Email检测等方法并不完善，若要应用请自行设计方法
四、编写用户登陆的Servlet：login.java
//login.java
//import required classes
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
import java.sql.*;
//class login
public class login extends HttpServlet
{
public void doGet(HttpServletRequest req,HttpServletResponse res)
throws IOException,ServletException
{
String username = req.getParameter("username");
String password = req.getParameter("password");
if(this.checklogin(username,password))
{
Cookie mylogin = new Cookie("username",username);
mylogin.setVersion(1);
mylogin.setPath("/");
mylogin.setComment("Your login username");
res.addCookie(mylogin);
}
//Cookie[] myCookies = req.getCookies();
//String nameValue = this.getCookieValue(myCookies,"username","not found");
//PrintWriter out = res.getWriter();
//out.println("username" + ":" + nameValue);
//out.println("Test Cookie Success!");
res.sendRedirect("/index.jsp");
}
public void doPost(HttpServletRequest req,HttpServletResponse res)
throws IOException,ServletException
{
doGet(req,res);
}
public static String getCookieValue(Cookie[] cookies,String cookieName,String defaultValue)
{
for(int i=0;i<cookies.length;i++) {
Cookie cookie = cookies[i];
if (cookieName.equals(cookie.getName()))
return(cookie.getValue());
}
return(defaultValue);
}
public boolean checklogin(String username,String password)
{
try{
DBConn loginConn = new DBConn();
loginConn.executeQuery("select * from tbl_user where name='" + username + "'");
if(loginConn.rs_next())
{
System.out.println("Connection created!");
if(loginConn.rs_getString("pwd").trim().equals(password))
{
System.out.println(loginConn.rs_getString("name"));
return true;
}
else
{
return false;
}
}
System.out.println("Test Login Success!");
return false;
}catch(Exception e){
System.out.println(e.toString());
return false;
}
}
public static void main(String args[])
{
login mylogin = new login();
System.out.println(mylogin.checklogin("shandong","shandong"));
}
}
说明：
1、默认的jdk1.4中并没有servlet包，请至sun公司网页下载servlet.jar，放至jdk目录下的jrelib目录下，并在JCreator中设置jdk处添加servlet.jar包
2、本Servlet用于检验用户名和密码，若正确则将用户名写入Cookie，完成后将当前页重定向到index.jsp页
五、编写检测用户是否已经登陆的bean：checkLogin.java
//checkLogin.java
//import required classes
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
//class checkLogin
public class checkLogin
{
public String username = "";
public boolean check(HttpServletRequest req,HttpServletResponse res)
throws IOException,ServletException
{
String cookieName = "username";
Cookie[] myCookies = req.getCookies();
this.username = this.getCookieValue(myCookies,cookieName,"not found");
PrintWriter out = res.getWriter();
if(this.username != null)
{
//out.println("早上好，" + this.username + "！");
return true;
}else{
out.println("登陆失败！");
return false;
}
}
public String getUserName()
{
return this.username;
}
public static String getCookieValue(Cookie[] cookies,String cookieName,String defaultValue)
{
for(int i=0;i<cookies.length;i++) {
Cookie cookie = cookies[i];
if (cookieName.equals(cookie.getName()))
