简易论坛javaweb程序

package it.com.db; import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import sun.security.timestamp.TSRequest; import it.com.com.Dbcon; public class UserDao { public List<Map> findAll(){ Dbcon db = new Dbcon(); Connection con=db.getcon(); String sql ="SELECT * FROM users"; List<Map> list = new ArrayList<Map>(); try { PreparedStatement pst=con.prepareStatement(sql); ResultSet rs = pst.executeQuery(); while(rs.next()){ Map map = new HashMap(); map.put("userName", rs.getString("userName")); map.put("userPwd", rs.getString("userPwd")); map.put("Ename", rs.getString("Ename")); map.put("Email", rs.getString("Email")); map.put("Logo", rs.getString("Logo")); list.add(map); } } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } return list; } public void resiger(String userName,String userPwd,String Ename,String Email,String Logo){ Dbcon db = new Dbcon(); Connection con=db.getcon(); String sql="INSERT INTO users (userName,userPwd,Ename,Email,Logo) VALUES (?,?,?,?,?)"; try { PreparedStatement pst = con.prepareStatement(sql); pst.setString(1,userName); pst.setString(2,userPwd); pst.setString(3,Ename); pst.setString(4,Email); pst.setString(5,Logo); pst.executeUpdate(); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } } public void update(String userName,String userPwd,String Ename,String Email,String Logo){ Dbcon db = new Dbcon(); Connection con=db.getcon(); String sql="UPDATE users SET userPwd=?,Ename=?,Email=?,Logo=? WHERE userName=? "; try { PreparedStatement pst=con.prepareStatement(sql); pst.setString(1, userPwd); pst.setString(2, Ename); pst.setString(3, Email); pst.setString(4, Logo); pst.setString(5, userName); pst.executeUpdate(); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } } public int pagesize(){ List<Map> list = findAll(); int pagesize=list.size(); int n=0; if(pagesize%5==0){ n=pagesize/5; }else{ n=pagesize/5+1; } return n; } public int deleteByName(String userName){ Dbcon db = new Dbcon(); Connection con=db.getcon(); String sql="DELETE FROM users WHERE userName=?"; int n=0; try { PreparedStatement pst=con.prepareStatement(sql); pst.setString(1, userName); pst.executeUpdate(); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); n=1; } return n; } public int login1(String username,String userpwd){ Dbcon db = new Dbcon(); Connection con=db.getcon(); String sql ="SELECT * FROM users WHERE userName=?"; int n=0; try { PreparedStatement pst=con.prepareStatement(sql); pst.setString(1, username); ResultSet rs = pst.executeQuery(); while(rs.next()){ n=1;//如果找到则执行 if(rs.getString("userPwd").equals(userpwd)){ n=2;//密码正确 }else{ n=3;//密码不正确 } } } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } return n; } public List<Map> select(String userName){ Dbcon db = new Dbcon(); Connection con=db.getcon(); List<Map> list =new ArrayList<Map>(); String sql="select * from users where userName=?"; try { PreparedStatement pst=con.prepareStatement(sql); pst.setString(1, userName); ResultSet rs = pst.executeQuery(); if(rs.next()){ Map map = new HashMap(); map.put("userName", rs.getString("userName")); map.put("userPwd", rs.getString("userPwd")); map.put("Ename", rs.getString("Ename")); map.put("Email", rs.getString("Email")); map.put("Logo", rs.getString("Logo")); list.add(map); } } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } return list; } public static void main(String[] args) { // TODO Auto-generated method stub UserDao us = new UserDao(); // List<Map> list=us.findAll(); // for(Map map:list){ // System.out.println(map); // } //us.update("x1", "xxx", "xxx", "xxx", "xxx"); //us.deleteByName("rt"); //us.resiger("asda", "sdad", "asda", "sdasd", "sdafdd", 221); // List<Map>list1= us.select("rgt"); // for(Map map:list1){ // System.out.println(map); // } // //us.resiger("x10", "xxx", "lala", "waa", "12"); } }