简单账号管理系统的实现（b/s、servlet、html、mysql）
????? 漫漫学习路，无处是尽头。“技术是学不完的，只能学会学习能力，并不断学习才是真”这句绝对的真理。总结的虽是，斌哥布置的练习，但完成这个练习的过程中，却真心是温习了很多，学习了很多。
????? 进入正题，下面总结下简单账号管理系统的实现过程。
????? 设计如下：
一、表结构
表名：userinfo
字段信息：id-int
?????????????? name-varchar
?????????????? password-varchar
二、模块结构
?? 1、数据操作模块
?????? 将数据库操作写在一个包下。
public class DAO {//创建arrylist用以存放查询结果 private ArrayList<Userinfo> al;/** * 插入数据到数据库中的方法 */ public ArrayList<Userinfo> add(Userinfo user){//获取数据库连接对象Connection conn=Until.getDBConnect();//sql操作数据String sql="insert into userinfo(name,pwd) values('"+user.name+"','"+user.password+"')";try {Statement stmt=conn.createStatement();int i=stmt.executeUpdate(sql);if(i>0){System.out.println("插入数据成功！");}//关闭数据库连接conn.close();} catch (Exception e) {// TODO Auto-generated catch blocke.printStackTrace();}return searchAll();}/** * 查询数据库所有数据 */ public ArrayList<Userinfo> searchAll(){ al=new ArrayList<Userinfo>();//获取数据库连接对象Connection conn=Until.getDBConnect();//sql操作数据String sql="select * from userinfo";try {Statement stmt=conn.createStatement();ResultSet rs=stmt.executeQuery(sql);while(rs.next()){Userinfo user=new Userinfo(rs.getInt("id"), rs.getString("name"),rs.getString("pwd"));this.al.add(user);}//清空结果集rs.close();//关闭数据库conn.close();} catch (Exception e) {// TODO Auto-generated catch blocke.printStackTrace();}return al;}/** * 按给定的id查询数据的方法 */ public ArrayList<Userinfo> searchById(int id){//获得数据库连接对象Connection conn=Until.getDBConnect();//操作数据String sql="select * from userinfo where id="+id;try {Statement stmt=conn.createStatement();ResultSet rs=stmt.executeQuery(sql);while(rs.next()){System.out.println("id="+rs.getInt("id")+",name="+rs.getString("name")+",password="+rs.getString(3));}conn.close();} catch (Exception e) {// TODO Auto-generated catch blocke.printStackTrace();}return searchAll();}/** * 删除指定id的数据的方法 */ public ArrayList<Userinfo> deleteById(int id){//获取数据库连接对象Connection conn=Until.getDBConnect();//操作数据String sql="delete from userinfo where id="+id;try {Statement stmt=conn.createStatement();int i=stmt.executeUpdate(sql);if(i>0){System.out.println("删除成功！！");}conn.close();} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}return searchAll();}/** * 根据指定id修改数据的方法 */ public ArrayList<Userinfo> updateById(int id,Userinfo user){//获取数据库连接对象Connection conn=Until.getDBConnect();//数据操作String sql="update userinfo set name=?,pwd=? where id=?";try {//预编译PreparedStatement ps=conn.prepareStatement(sql);//设置对象参数ps.setString(1, user.name);ps.setString(2, user.password);ps.setInt(3, id);int i=ps.executeUpdate();if(i>0){System.out.println("数据修改成功！");}conn.close();} catch (Exception e) {// TODO Auto-generated catch blocke.printStackTrace();}return searchAll();}}?
?2、用5个servlet、2个html页面进行页面
5个servlet：Userinfo-用户列表servlet-用于查找并显示所有用户
?????????????????? Deleteservlet-删除操作servlet-用于删除指定用户
?????????????????? Updateservlet-更新操作servlet-用于更新指定用户信息
?????????????????? Regesiterservlet-添加操作（注册）servlet-用于注册新用户
?????????????????? Logincheck-用户身份验证servlet-用于验证登陆用户是否为注册用户
2个html：page.html-登陆页面
?????????????? register.html-注册页面
3、系统各页面交互流程
?4、代码示例
userinfo：
/**显示用户servlet：用于显示当前全部用户信息 * Servlet implementation class Userinfo */public class Userinfo extends HttpServlet { DAO dao=new DAO(); /** * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response) */protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {//设置响应文本字符集response.setContentType("text/html;charset=gbk");PrintWriter out=response.getWriter();//创建arraylist来接收查询结果ArrayList<test1_db.Userinfo> al_temp=dao.searchAll();//拼出显示页面out.println("<!DOCTYPE HTML PUBLIC"-//W3C//DTD HTML 4.01 Transitional//EN">");out.println("<html>");out.println("<head><title>Userinfo</title></head>");out.println("<body>");out.println("userinfo show as follows:");out.println("<table border="5"width="250px"bgcolor="green"bordercolor="gray">");out.println("<tr><td>ID</td><td>姓名</td><td>密码</td><td>操作</td><td>操作</td></tr>");//循环查询用户信息以显示for(int i=0;i<al_temp.size();i++){test1_db.Userinfo user_temp=al_temp.get(i);int id=user_temp.id;String name=user_temp.name;String password=user_temp.password;out.println("<tr><td>"+id+"</td><td>"+name+"</td><td>"+password+"</td><td><a href='Deleteservlet?id="+id+" '>删除用户</a></td><td><a href='Updateservlet?id="+id+"'>修改信息</a></td></tr>");}out.println("</border>");out.println("</table>");out.println("</body>");out.println("</html>");}?logincheck：
/** * Servlet implementation class Logincheck */public class Logincheck extends HttpServlet {private static final long serialVersionUID = 1L; DAO dao=new DAO(); protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {response.setContentType("text/html;charset=gbk");PrintWriter out=response.getWriter();//获得参数String name=request.getParameter("username");String password=request.getParameter("password");//创建用户列表以存放查询结果ArrayList<test1_db.Userinfo> al_temp=dao.searchAll();//循环得到每条记录以验证身份for(int i=0;i<al_temp.size();i++){test1_db.Userinfo user_temp=al_temp.get(i);//判断用户名和密码是否存在if(user_temp.name.equals(name)&&user_temp.password.equals(password)){//是，则跳转到用户列表servlet并跳出循环response.sendRedirect("Userinfo");break;}}//否，则拼出提示页面out.println("<!DOCTYPE HTML PUBLIC"-//W3C//DTD HTML 4.01 Transitional//EN">");out.println("<html>");out.println("<body>");out.println("用户不存在，请注册……");out.println("<p><a href='register.html'>注册</a></p>");out.println("</body>");out.println("</html>");}?updateservlet：
/** * Servlet implementation class Updateservlet */public class Updateservlet extends HttpServlet {private static final long serialVersionUID = 1L;DAO dao = new DAO();/** * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse * response) */protected void doGet(HttpServletRequest request,HttpServletResponse response) throws ServletException, IOException {response.setContentType("text/html;charset=gbk");PrintWriter out = response.getWriter();//获得来自于用户列表servlet的参数idString id_temp = request.getParameter("id");int id = Integer.parseInt(id_temp);//创建arraylist以存放查找的对应id的记录ArrayList<test1_db.Userinfo> al_temp = dao.searchById(id);//拼出查找结果显示页面out.println("<!DOCTYPE HTML PUBLIC"-//W3C//DTD HTML 4.01 Transitional//EN">");out.println("<html>");out.println("<head><title>Update</title></head>");out.println("<body>");out.println("please recorrect the information as follows:");out.println("<table border="5"width="250px"bgcolor="green"bordercolor="gray">");out.println("<tr><td>ID</td><td>姓名</td><td>密码</td></tr>");//获得查找结果集中的参数以用于传入“修改”响应test1_db.Userinfo user = al_temp.get(0);String name = user.name;String password = user.password;String username = "username";String userpassword = "userpassword";// 1、重写url传值//out.println("<form action='Updateservlet?id=" + user.id//+ "' method='post'>");//out.println("<tr><td >" + id + "</td><td><input type='text' name='"//+ username + "' value='" + name//+ "'><br></td><td><input type='text' name='" + userpassword//+ "' value='" + password + "'><br></td></tr>");// 2、表单传值out.println("<form action='Updateservlet' method='post'>");out.println("<tr><td >" + id + "</td><td><input type='text' name='"+ username + "' value='" + name+ "'><br></td><td><input type='text' name='" + userpassword+ "' value='" + password + "'><br></td></tr>");out.println("<input type='hidden' name='id' value='" + id + "'>");out.println("<input type='submit' value='提交'><input type='reset' name='reset'>");out.println("</form>");out.println("</border>");out.println("</table>");out.println("</body>");}/** * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse * response) */protected void doPost(HttpServletRequest request,HttpServletResponse response) throws ServletException, IOException {//获得updateservlet中传入的更新数据所需的参数String name_update = request.getParameter("username");String password_update = request.getParameter("userpassword");String id_update = request.getParameter("id");int id = Integer.parseInt(id_update);//创建更新后的用户对象、执行更新操作并跳转页面到用户列表servlettest1_db.Userinfo user_update = new test1_db.Userinfo(id, name_update,password_update);dao.updateById(id, user_update);response.sendRedirect("Userinfo");}}?registerservlet：
/** * Servlet implementation class Register */public class Register extends HttpServlet {private static final long serialVersionUID = 1L; DAO dao=new DAO(); /** * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response) */protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {//获得参数String username=request.getParameter("username");String password=request.getParameter("password");//创建要添加的用户对象test1_db.Userinfo user_temp=new test1_db.Userinfo(username, password);dao.add(user_temp);//跳转回登陆界面response.sendRedirect("page.html");}?deleteservlet：
/** * Servlet implementation class Deleteservlet */public class Deleteservlet extends HttpServlet {private static final long serialVersionUID = 1L; /** * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response) */protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {response.setCharacterEncoding("gbk");PrintWriter out=response.getWriter();out.println("进入删除servlet！");//获得需删除的用户信息的idString id_temp=request.getParameter("id");int id=Integer.parseInt(id_temp);DAO dao=new DAO();dao.deleteById(id);//跳转回用户显示servletresponse.sendRedirect("Userinfo");}? 1 楼 lovebegar 2012-05-21 这些简单的东西也要学习下~ 2 楼 JuliaAilse 2012-05-21 lovebegar 写道这些简单的东西也要学习下~