javaweb+jsp

package cn.edu.lingnan.dao; import cn.edu.lingnan.dto.User; import java.io.UnsupportedEncodingException; import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; import java.util.Scanner; import java.util.Vector; import cn.edu.lingnan.util.DataAccess; public class UserDao { public String login(String username,String password){ String superuser=null; Connection conn=null; PreparedStatement prep=null; ResultSet rs=null; try{ conn=DataAccess.getConnection(); System.out.println(conn.toString()); prep=conn.prepareStatement ("select * from user where username = ? and password = ?"); prep.setString(1,username); prep.setString(2,password); rs=prep.executeQuery(); if(rs.next()){ superuser=rs.getString("superuser"); System.out.println("superuser "+superuser); } }catch(SQLException e){ e.printStackTrace(); }finally{ try{ if(prep!=null){ prep.close(); } if (rs!=null) { rs.close(); } } catch(SQLException e){ e.printStackTrace(); } } return superuser; } public boolean register(User u) { boolean flag=false; Connection conn=null; PreparedStatement prep=null; try{ conn=DataAccess.getConnection(); prep=conn.prepareStatement ("insert into user values(?,?,?)"); prep.setString(1,u.getUsername()); prep.setString(2,u.getPassword()); prep.setString(3, u.getSuperuser()); prep.execute(); flag=true; }catch(SQLException e){ e.printStackTrace(); }finally{ try{ if(prep!=null){ prep.close(); prep=null; } if (conn!=null) { conn.close(); conn=null; } } catch(SQLException e){ e.printStackTrace(); } } return flag; } private static Scanner in=new Scanner(System.in); public User getUserInfoByname(String username){ User u =new User(); Connection conn=null; Statement stat=null; ResultSet rs=null; try{ conn=DataAccess.getConnection(); stat=conn.createStatement(); rs=stat.executeQuery ("select * from User name='"+username+"'"); while(rs.next()){ u.setUsername(rs.getString("username")); u.setPassword(rs.getString("password")); u.setSuperuser(rs.getString("superuser")); } }catch(SQLException e){ e.printStackTrace(); }finally{ try{ if(rs!=null){ rs.close(); rs=null; } if(stat!=null){ stat.close(); stat=null; } if(conn!=null){ conn.close(); conn=null; } }catch(SQLException e){ e.printStackTrace(); } } return u; } //**********获取学生信息*********** public Vector<User> getAllUserInfo() throws UnsupportedEncodingException{ Vector<User> v=new Vector<User>(); Connection conn=null; Statement stat=null; ResultSet rs=null; try{ conn=DataAccess.getConnection(); stat=conn.createStatement(); rs=stat.executeQuery ("select * from User"); while(rs.next()){ User u=new User(); String str = rs.getString("username"); str = new String(str.getBytes("ISO-8859-1"),"GBK"); u.setUsername(str); u.setPassword(rs.getString("password")); u.setSuperuser(rs.getString("superuser")); v.add(u); } }catch(SQLException e){ e.printStackTrace(); }finally{ try{ if(rs!=null){ rs.close(); rs=null; } if(stat!=null){ stat.close(); stat=null; } if(conn!=null){ conn.close(); conn=null; } }catch(SQLException e){ e.printStackTrace(); } } return v; } private static boolean addUserInfo(String username,String password,String superuser){ Connection conn=null; Statement stat=null; ResultSet rs=null; PreparedStatement us=null; try{ conn=DataAccess.getConnection(); stat=conn.createStatement(); rs = stat.executeQuery ("select userid from User where name='"+username+"'"); if(rs.next()){ System.out.println("——插入失败，该用户已经存在——"); }else{ us=conn.prepareStatement ("insert into User values(?,?,?)"); us.setString(1, username); us.setString(2, password); us.setString(3,superuser); us.executeUpdate(); } }catch(SQLException e){ e.printStackTrace(); }finally{ try{ if(rs!=null){ rs.close(); rs=null; } if(stat!=null){ stat.close(); stat=null; } if(conn!=null){ conn.close(); conn=null; } }catch(SQLException e){ e.printStackTrace(); } } return true; } public void executeaddUserInfo(){ System.out.println("请输入用户姓名："); String username=in.next(); System.out.println("请输入用户密码："); String password=in.next(); System.out.println("请输入用户权限："); String superuser=in.next(); if(addUserInfo(username,password,superuser)){ System.out.println("插入用户数据成功!!"); }else{ System.out.println("插入用户数据失败!!"); } } private boolean deteleUserInfo(String username){ int flag=0; Connection conn=null; Statement stat=null; ResultSet rs=null; PreparedStatement us=null; try{ conn=DataAccess.getConnection(); stat=conn.createStatement(); rs = stat.executeQuery ("select name from User where isDelete=1 and name='"+username+"'"); if(rs.next()){ us=conn.prepareStatement ("update User set isDetelt=? where name=?"); us.setInt(1,0); us.setString(2,username); us.executeUpdate(); flag=1; } }catch(SQLException e){ e.printStackTrace(); }finally{ try{ if(rs!=null){ rs.close(); rs=null; } if(stat!=null){ stat.close(); stat=null; } if(conn!=null){ conn.close(); conn=null; } }catch(SQLException e){ e.printStackTrace(); } } if(flag==0) return false; else return true; } public void executeDeleteUserInfo(){ System.out.println("——请输入你所要删除的用户name——"); String str=in.next(); if(deteleUserInfo(str)){ System.out.println("——删除失败，该用户不存在——"); }else{ System.out.println("——删除成功——"); } } private boolean updateUserInfo(String username,String password,String superuser){ Connection conn=null; Statement stat=null; ResultSet rs=null; PreparedStatement us=null; try{ conn=DataAccess.getConnection(); stat=conn.createStatement(); rs = stat.executeQuery ("selct * from User name='"+username+"'"); if(rs.next()){ us=conn.prepareStatement ("update User set password=? and superuser=? where username=?"); us.setString(1,username); us.setString(2,superuser); } }catch(SQLException e){ e.printStackTrace(); }finally{ try{ if(rs!=null){ rs.close(); rs=null; } if(stat!=null){ stat.close(); stat=null; } if(conn!=null){ conn.close(); conn=null; } }catch(SQLException e){ e.printStackTrace(); } } return true; } public void executeupdateUserInfo(){ System.out.println("——请输入你所需要修改的用户名——"); String username=in.next(); System.out.println("——请输入你所需要修改的用户密码——"); String password=in.next(); System.out.println("——请输入你所需要修改的用户权限——"); String superuser=in.next(); if(updateUserInfo(username,password,superuser)){ System.out.println("——用户数据更新成功——"); }else{ System.out.println("——用户数据更新失败——"); } } }