UserManager
刚刚学习servlet,打算学做一个小项目把前边学到的知识做一个总结.
由于只是实现了一些简单的功能,所以美工就凑合着看吧(美工其实也不太会).
首先项目整体架构如图
项目准备工作:
要用到mysql数据库,所以要导入
直接复制在webroot/web-inf/lib下
然后创建Users库,user表
CREATE DATABASE Users;
USE Users;
CREATE TABLE USER(
id INT PRIMARY KEY AUTO_INCREMENT,//主键
username VARCHAR(32) NOT NULL,//用户名
email VARCHAR(64) NOT NULL,//邮箱
grade INT DEFAULT 1,//级别
PASSWORD VARCHAR(32) NOT NULL//密码 );
事先插入一些用户
INSERT INTO USER(username,email,PASSWORD) VALUES ("mahui","1130804967@sohu.com","123"),
("aaaa","1130804967@sina.com","123"),
("bbbb","1130804967@baidu.com","123"),
("cccc","1130804967@google.com","123"),
("dddd","1130804967@163.com","123");
1.LoginServlet.java
package com.mh.view; import java.io.IOException;
import java.io.PrintWriter; import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse; public class LoginServlet extends HttpServlet { private static final long serialVersionUID = 1L; public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException { response.setContentType("text/html;charset =UTF-8");
request.setCharacterEncoding("UTF-8");
PrintWriter out = response.getWriter(); out.println("<h1>登录界面<h1>"); out.println("<form action = '/UsersManager/LoginClServlet' method = 'post'>");//form表单提交到LoginClServlet.java
out.println("I D:<input type = 'text' name = 'id'/><br/>");
out.println("密 码:<input type = 'password' name = 'password'/><br/>");
out.println("<input type = 'submit' value = 'Submit'/>");
out.println("</form>");
String errInfo =(String)request.getAttribute("err");//第一次该属性为null,什么都不显示
if(errInfo != null){
out.println("<font color = 'red'>"+errInfo+"<font>");//如果errinfo不为空,则输出错误信息
} } public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException { } }
2.LoginClServlet.java(该servlet用于简易的处理用户登录信息)
package com.mh.controller; import java.io.IOException;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException; import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse; public class LoginClServlet extends HttpServlet { private static final long serialVersionUID = 1L; public final static String URL = "jdbc:mysql://localhost:3306/Users";//建立连接 public final static String USER = "root";//用户 public final static String PASSWORD = "334400";//密码 public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
request.setCharacterEncoding("UTF-8"); String id = request.getParameter("id");//获取id
String pass = request.getParameter("password");//获取密码 Connection conn = null;
PreparedStatement prep = null;
ResultSet set = null;
try{
Class.forName("com.mysql.jdbc.Driver");//加载驱动 conn = DriverManager.getConnection(URL,USER,PASSWORD);//获得与数据库的连接对象conn prep = conn.prepareStatement("select * from User where id = ? and password = ?");//预处理语句 prep.setString(1,id);//第一个?赋值
prep.setString(2,pass);//第二个?赋值 set = prep.executeQuery();//执行查询 if(set.next()){//如果结果集合存在用户
request.getRequestDispatcher("/MainFrame").forward(request,response);//转发到/MainFrame主页面
}else{
request.setAttribute("err", "用户ID或密码有误!");//如果不存在该用户,则设置err属性的信息
request.getRequestDispatcher("/LoginServlet").forward(request, response);//转发到登录界面
} }catch(Exception e){
e.printStackTrace();
}finally{
//以下为关闭资源
if(set != null){
try {
set.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
if(prep != null){
try {
prep.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
if(conn != null){
try {
conn.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
} } public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException { doGet(request,response);
} }
3.MainFrame.java
package com.mh.view; import java.io.IOException;
import java.io.PrintWriter; import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse; public class MainFrame extends HttpServlet { private static final long serialVersionUID = 1L; public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException { response.setContentType("text/html;charset=UTF-8");
request.setCharacterEncoding("utf-8");
PrintWriter out = response.getWriter();
//这里没什么好讲的,都是一些链接
out.println("<h1>登陆成功<h1>");
out.println("<h3>请选择一下操作<h3>");
out.println("<a href = '/UsersManager/ManageUsers'>管理用户</a>");//跳转到管理界面
out.println("<a href = '/UsersManager/AddUserMain'>添加用户</a>");//添加用户
out.println("<a href = '/UsersManager/SelectUsers'>查询用户</a>");//查询
out.println("<a href = '/UsersManager/LoginServlet'>安全退出</a>");//退出 } public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doGet(request,response); } }
4.跳转到管理用户页面,这里边是逻辑比较复杂的一个页面,因为页面和逻辑没有实现分离,还有里边使用了分页,mysql的分页是依靠limit来实现
package com.mh.view; import java.io.IOException;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException; import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse; public class ManageUsers extends HttpServlet { private static final long serialVersionUID = 1L; public final static String URL = "jdbc:mysql://localhost:3306/Users"; public final static String USER = "root"; public final static String PASSWORD = "334400"; public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException { response.setContentType("text/html;charset=utf-8");
PrintWriter out = response.getWriter();
//以下四行代码实现了跳转功能,document.getElementById('pageNow')首先获得你要跳转的页面,然后在本页面(_self参数控制)打开一个新的页面,并把page当成参数传给本页面
out.print("<script type = 'text/javascript' language = 'javascript'>");
out.print("function go(){var page = document.getElementById('pageNow');"
+ "window.open('/UsersManager/ManageUsers?page='+page.value,'_self');}");
out.print("</script>"); out.println("<h1>用户管理</h1><a href = '/UsersManager/MainFrame'>主页面</a><hr/>"); out.println("<table border = 1 width = 500px>"); out.println("<tr><th>ID</th><th>用户名</th><th>Email</th><th>级别</th></tr>"); Connection conn = null;
PreparedStatement prep = null;
ResultSet set = null;
try{
Class.forName("com.mysql.jdbc.Driver"); conn = DriverManager.getConnection(URL,USER,PASSWORD); prep = conn.prepareStatement("select count(id) from User ");//获得总共有多少条记录,为分页做准备 set = prep.executeQuery(); set.next();//这里要注意,因为光标是指向集合第一条记录的前面,所以要执行next()方法
int rowCount = set.getInt(1);//把总数赋值给rowcount int pageSize = 3;//每页显示几条记录 int pageCount = (rowCount-1)/pageSize + 1;//总共有几页(这里用到了一个小算法) int pageCurr = 1;//当前页 String curr_Page = (String) request.getParameter("page");//这里是为了获取用户点击下边的第i页跳转到本页面提交的page参数 if(curr_Page != null){
pageCurr = Integer.parseInt(curr_Page);//第一次该参数为null,以后根据用户点击的页数而定
} prep.close();//先关闭
set.close(); String sql = "select * from User limit "+(pageCurr-1)*pageSize+ ","+pageSize;//这里分页用到了limit,使用limit (第几页-1)*每页显示的记录,每页显示记录数
prep = conn.prepareStatement(sql);//再次预处理新的sql set = prep.executeQuery();//执行 while(set.next()){//这里得到的set结果集是一个集合,所以使用while循环
out.println("<tr><td>"+set.getInt(1)+"</td><td>"
+set.getString(2)+"</td><td>"+set.getString(3)
+"</td><td>"+set.getString(4)+"</td></tr>");
}
out.println("</table><br/>");
if(pageCurr != 1){
out.print("<a href = '/UsersManager/ManageUsers?page="+(pageCurr-1)+"'>上一页 </a>");
}
//这里是表格的下边把总页数以for循环的方式创建超链接
for(int i = 1; i <= pageCount; i++){////如果不等于第一页,则显示,否则隐藏
out.print("<a href = '/UsersManager/ManageUsers?page="+i+"'><"+i+"></a>");
}
if(pageCurr != pageCount){//如果不等于最后一页,则显示,否则隐藏
out.print("<a href = '/UsersManager/ManageUsers?page="+(pageCurr+1)+"'>下一页 </a>");
} out.print("当前页"+pageCurr+"/总页数"+pageCount);
//下边是一个跳转功能,要用到javascript,给按钮增加一个点击事件,一点击该按钮,则调用go()方法,该方法在代码的头部
out.print("<br/>跳转到");
out.print("<input type = 'text' size = '20px' id = 'pageNow'/>");
out.print(" <input type = 'button' value = 'GO' onclick = 'go()'/>");
}catch(Exception e){
e.printStackTrace();
}finally{
//关闭资源
if(set != null){
try {
set.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
if(prep != null){
try {
prep.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
if(conn != null){
try {
conn.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
} public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doGet(request,response); } }
5.AddUserMain.java 没什么好说的
package com.mh.view; import java.io.IOException;
import java.io.PrintWriter; import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse; public class AddUserMain extends HttpServlet { private static final long serialVersionUID = 1L; public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html;charset=utf-8");
PrintWriter out = response.getWriter(); out.print("<h1>添加用户</h1><br/><hr/>");
out.print("<form action = '/UsersManager/AddUserHandle' method = 'post'>Name:<input type = 'text' name = 'name'/><br/>");
out.print("Email:<input type = 'text' name = 'email'/><br/>");
out.print("PassWord:<input type = 'password' name = 'password'/><br/>");
out.print("<input type = 'submit' value = 'Submit'/>"); out.print("</form>"); } public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException { doGet(request,response);
} }
6.AddUserHandle.java
package com.mh.controller; import java.io.IOException;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException; import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse; public class AddUserHandle extends HttpServlet { private static final long serialVersionUID = 1L; public final static String URL = "jdbc:mysql://localhost:3306/Users"; public final static String USER = "root"; public final static String PASSWORD = "334400"; public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException { response.setContentType("text/html;charset=utf-8"); String username = new String(request.getParameter("name").getBytes("ISO-8859-1"),"UTF-8") ;//获取用户名,这样写是为了用户输入的中文乱码
String email = request.getParameter("email");//获取邮箱
String password = request.getParameter("password");//获取密码 int row = 0;
Connection conn = null;
PreparedStatement prep = null;
ResultSet set = null;
try{
Class.forName("com.mysql.jdbc.Driver"); conn = DriverManager.getConnection(URL,USER,PASSWORD); prep = conn.prepareStatement("insert into User (username,email,password)values(?,?,?)");//预处理 prep.setString(1,username);//赋值
prep.setString(2,email);
prep.setString(3, password); row = prep.executeUpdate();//执行更新,返回一个整数 if(row != 0){//插入成功返回到ManageUsers.java
request.getRequestDispatcher("/ManageUsers").forward(request,response);
}else{
//录入失败返回本界面
request.getRequestDispatcher("/AddUserMain").forward(request, response);
} }catch(Exception e){
e.printStackTrace();
}finally{
//关闭资源
if(set != null){
try {
set.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
if(prep != null){
try {
prep.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
if(conn != null){
try {
conn.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
} } public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException { doGet(request,response);
} }
7.SelectUsers.java
package com.mh.view; import java.io.IOException;
import java.io.PrintWriter; import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse; public class SelectUsers extends HttpServlet { private static final long serialVersionUID = 1L; public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException { response.setContentType("text/html;charset=utf-8");
PrintWriter out = response.getWriter();
out.print("<h1>查找用户</h1><br/><hr/>");
out.print(" <a href = '/UsersManager/MainFrame'>主页面</a>");
out.print("<form action = '/UsersManager/SelectHandle' method = 'post'>");//跳转到SelectHandle.java
out.print("请输入关键字 <input type = 'text' size = '10px' name = 'key'/>");
out.print(" <input type = 'submit' value = '查找'/>");
out.print("</form>");
} public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException { doGet(request,response);
} }
8.SelectHandle.java
package com.mh.controller; import java.io.IOException;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException; import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse; public class SelectHandle extends HttpServlet { private static final long serialVersionUID = 1L; public final static String URL = "jdbc:mysql://localhost:3306/Users"; public final static String USER = "root"; public final static String PASSWORD = "334400"; public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException { response.setContentType("text/html;charset=utf-8"); PrintWriter out = response.getWriter(); String key = new String(request.getParameter("key").getBytes("ISO-8859-1"),"UTF-8") ; Connection conn = null;
PreparedStatement prep = null;
ResultSet set = null;
try{
Class.forName("com.mysql.jdbc.Driver"); conn = DriverManager.getConnection(URL,USER,PASSWORD); prep = conn.prepareStatement("select * from User where username like ?");//模糊查询username prep.setString(1,"%"+key+"%");//模糊查询格式
set = prep.executeQuery();
out.print("<h1>查询结果</h1><br/><hr/>");
out.print(" <a href = '/UsersManager/SelectUsers'>返回</a>");
out.println("<table border = 1 width = 500px>"); out.println("<tr><th>ID</th><th>用户名</th><th>Email</th><th>级别</th></tr>"); while(set.next()){//返回集合,遍历
out.println("<tr><td>"+set.getInt(1)+"</td><td>"
+set.getString(2)+"</td><td>"+set.getString(3)
+"</td><td>"+set.getString(4)+"</td></tr>");
}
out.println("</table><br/>"); }catch(Exception e){
e.printStackTrace();
}finally{
if(set != null){
try {
set.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
if(prep != null){
try {
prep.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
if(conn != null){
try {
conn.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
} } public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException { doGet(request,response);
} }
UserManager的更多相关文章
- CoreCRM 开发实录 —— 单元测试之 Mock UserManager 和 SignInManager
单元测试的核心就是:只测试眼前的逻辑.这就要求所有的依赖项都要使用仿类来代替,也就是所谓的 Mock Object.在测试 ProfileRepository 和 AccountController ...
- 解决EJB本地调用“java.lang.ClassCastException: $Proxy96 cannot be cast to com.tgb.ejb.UserManager”异常
EJB本地调用方式:把Webclient和EJB服务端部署到同一个JBoss,client和server通过一个JVM进行通信. Web客户端本地调用时.需引用EJB服务端打包的jar,不需引用JBo ...
- InvalidOperationException: Unable to resolve service for type 'Microsoft.AspNetCore.Identity.UserManager`1[Microsoft.AspNetCore.Identity.IdentityUser]'
在新建asp.net core 应用后, 添加了自定义的ApplicationDbContext 和ApplicationUser ,并添加了Identity认证后, 会出现 InvalidOpera ...
- win10系统中UserManager 总是被禁用怎么解决?
RT,也就是提示win10开始菜单和cortana无法工作.升级win10后一直被这个问题困扰,论坛也见有人发帖求助这类问题,百度了方法打开任务管理器进入服务更改User Manager启动类型为自动 ...
- .NET Core中的认证管理解析
.NET Core中的认证管理解析 0x00 问题来源 在新建.NET Core的Web项目时选择“使用个人用户账户”就可以创建一个带有用户和权限管理的项目,已经准备好了用户注册.登录等很多页面,也可 ...
- ASP.NET Core 之 Identity 入门（三）
前言 在上一篇文章中,我们学习了 CookieAuthentication 中间件,本篇的话主要看一下 Identity 本身. 最早2005年 ASP.NET 2.0 的时候开始, Web 应用程序 ...
- 从Membership 到 .NET4.5 之 ASP.NET Identity
我们前面已经讨论过了如何在一个网站中集成最基本的Membership功能,然后深入学习了Membership的架构设计.正所谓从实践从来,到实践从去,在我们把Membership的结构吃透之后,我们要 ...
- 年度巨献-WPF项目开发过程中WPF小知识点汇总（原创+摘抄）
WPF中Style的使用 Styel在英文中解释为”样式“,在Web开发中,css为层叠样式表,自从.net3.0推出WPF以来,WPF也有样式一说,通过设置样式,使其WPF控件外观更加美化同时减少了 ...
- [Android]使用Dagger 2来构建UserScope（翻译）
以下内容为原创,欢迎转载,转载请注明 来自天天博客:http://www.cnblogs.com/tiantianbyconan/p/6237731.html 使用Dagger 2来构建UserSco ...
随机推荐
- golang mutex互斥锁分析
互斥锁:没有读锁写锁之分,同一时刻,只能有一个gorutine获取一把锁 数据结构设计: type Mutex struct { state int32 // 将一个32位整数拆分为 当前阻塞的gor ...
- python的tkinter版本不匹配问题:RuntimeError: test:tk.h version (8.4) doesn't match libtk.a version (8.5)
Traceback (most recent call last): File "/root/CodeWorkPace/test/TCPClient.py", line 20, i ...
- 编写PHP代码总结
1- 编写模块化代码 良好的PHP代码应该是模块化代码.PHP的面向对象的编程功能是一些特别强大的工 具,可以把你的应用程序分解成函数或方法.你应该尽可能多的从你的应用程序的服务器端分开前端的HTML ...
- 使用MyBatis对数据库中表实现CRUD操作（二）
一.使用MyBatis对表实现CRUD操作 1.定义sql映射 userMapper.xml <?xml version="1.0" encoding="UTF-8 ...
- kvm的sshd起不来
同事不知道在一台KVM虚拟机执行了chmod -R 777 / 将更目录中的所有文件的权限都改为777,重启该虚拟机之后发现该虚拟机登不上去了,来找我,我尝试重启了几次虚拟机之后,发现总是可以被pi ...
- 腾讯云总监手把手教你，如何成为AI工程师？
作者:朱建平 腾讯云技术总监,腾讯TEG架构平台部专家工程师 1.关于人工智能的若干个错误认知 人工智能是AI工程师的事情,跟我没有什么关系 大数据和机器学习(AI) 是解决问题的一种途径和手段,具有 ...
- 【iOS】7.4 定位服务->3.1 地图框架MapKit 功能1：地图展示
> 本文并非最终版本,如果想要关注更新或更正的内容请关注文集,联系方式详见文末,如有疏忽和遗漏,欢迎指正. --- > 本文相关目录: ================== 所属文集:[[ ...
- sql server删除主键约束所想到的
从网上找到了下面一段代码: declare @Pk varchar(100);select @Pk=Name from sysobjects where Parent_Obj=OBJECT_ID('表 ...
- 【原创】Octovis在Ubuntu16.04下运行出现core dump的解决方案
本人SLAM研究新手,使用系统为Ubuntu16.04.本文原址:http://www.cnblogs.com/hitlrk/p/6667253.html 在学习SLAM的过程中,使用Octomap进 ...
- poptest老李谈jvm的GC
poptest老李谈jvm的GC poptest是国内唯一一家培养测试开发工程师的培训机构,以学员能胜任自动化测试,性能测试,测试工具开发等工作为目标.如果对课程感兴趣,请大家咨询qq:90882 ...