java + sql 银行管理系统

package MyDemo; import java.sql.*; public class Denlu { public Denlu(){ } public static int shanchu(String id) { long a=chaxun(); if(a==0) { try{ Class.forName("com.mysql.jdbc.Driver"); Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/ren","root",""); Statement stmt=conn.createStatement(); String sql="delete from tablename where UserID='"+Integer.parseInt(id)+"'"; stmt.executeUpdate(sql); stmt.close(); conn.close(); return 1; } catch(Exception sqle){ System.err.println(sqle); return 3; } } else return 2; } public static int zhucezh(String name,String sex,String kahao,String mima,String phone) {try{ //1.注册驱动 String driverClassName = "com.mysql.jdbc.Driver"; Class.forName("com.mysql.jdbc.Driver"); //2.连接数据库 Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/ren","root",""); Statement stmt=conn.createStatement(); String sql="insert into tablename values(?,?,?,?,?,?)"; PreparedStatement ps=(PreparedStatement) conn.prepareStatement(sql); ps.setString(1,kahao); ps.setString(2,name); ps.setString(3,mima); ps.setString(4,phone); ps.setString(5,sex); ps.setInt(6,0); ps.executeUpdate(); ps.close(); stmt.close(); conn.close(); return 1; } catch(Exception sqle){ System.err.println(sqle); return 3; } } public static int chagai(String name,String sex,String phone) { try{ //1.注册驱动 String driverClassName = "com.mysql.jdbc.Driver"; Class.forName("com.mysql.jdbc.Driver"); //2.连接数据库 Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/ren","root",""); Statement stmt=conn.createStatement(); ResultSet rs=stmt.executeQuery("select * from tablename where UserID='"+Integer.parseInt(a.Kahao.getText())+"'"); if(rs.next()) { stmt.executeUpdate("Update tablename set Usersex='"+sex+"',Username='"+name+"',Userphone='"+phone+"' where UserID='"+Integer.parseInt(a.Kahao.getText())+"'"); rs.close(); stmt.close(); conn.close(); return 1; } } catch(Exception sqle){ System.err.println(sqle); return 3; } return 2; } public static int gaimi(String y,String x) { long p; p=checkUser(a.Kahao.getText(),y); if(p==1) { try{ //1.注册驱动 String driverClassName = "com.mysql.jdbc.Driver"; Class.forName("com.mysql.jdbc.Driver"); //2.连接数据库 Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/ren","root",""); Statement stmt=conn.createStatement(); ResultSet rs=stmt.executeQuery("select * from tablename where UserID='"+Integer.parseInt(a.Kahao.getText())+"'"); if(rs.next()) { stmt.executeUpdate("Update tablename set UserPW='"+x+"' where UserID='"+Integer.parseInt(a.Kahao.getText())+"'"); rs.close(); stmt.close(); conn.close(); return 1; } } catch(Exception sqle){ System.err.println(sqle); return 3; } } return 2; } public static long chaxun() { long j; try{ //1.注册驱动 String driverClassName = "com.mysql.jdbc.Driver"; Class.forName("com.mysql.jdbc.Driver"); //2.连接数据库 Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/ren","root",""); Statement stmt=conn.createStatement(); ResultSet rs=stmt.executeQuery("select * from tablename where UserID='"+Integer.parseInt(a.Kahao.getText())+"'"); if(rs.next()) { j=rs.getInt("Useryue"); rs.close(); stmt.close(); conn.close(); return j; } } catch(Exception sqle){ System.err.println(sqle); return -2; } return -2; } public static int qukuan(long k,long j) { try{ //1.注册驱动 String driverClassName = "com.mysql.jdbc.Driver"; Class.forName("com.mysql.jdbc.Driver"); //2.连接数据库 Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/ren","root",""); Statement stmt=conn.createStatement(); ResultSet rs=stmt.executeQuery("select * from tablename where UserID='"+k+"'"); if(rs.next()) { j=rs.getInt("Useryue")-j; if(j<0) return 2; stmt.executeUpdate("Update tablename set Useryue='"+j+"' where UserID='"+k+"'"); rs.close(); stmt.close(); conn.close(); return 1; } } catch(Exception sqle){ System.err.println(sqle); return 3; } return 0; } public static int cunkuan(long k,long j) { try{ //1.注册驱动 String driverClassName = "com.mysql.jdbc.Driver"; Class.forName("com.mysql.jdbc.Driver"); //2.连接数据库 Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/ren","root",""); Statement stmt=conn.createStatement(); ResultSet rs=stmt.executeQuery("select * from tablename where UserID='"+k+"'"); if(rs.next()) { j=rs.getInt("Useryue")+j; stmt.executeUpdate("Update tablename set Useryue='"+j+"' where UserID='"+k+"'"); rs.close(); stmt.close(); conn.close(); return 1; } } catch(Exception sqle){ System.err.println(sqle); return 2; } return 0; } public static int zhuanzhang(long k,long j) { long i = 0; long p = 0; i=Denlu.cunkuan(k, 0); if(i==1) { p=Denlu.qukuan(Integer.parseInt(a.Kahao.getText()), j); if(p==1) { try{ //1.注册驱动 String driverClassName = "com.mysql.jdbc.Driver"; Class.forName("com.mysql.jdbc.Driver"); //2.连接数据库 Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/ren","root",""); Statement stmt=conn.createStatement(); ResultSet rs=stmt.executeQuery("select * from tablename where UserID='"+k+"'"); if(rs.next()) { j=rs.getInt("Useryue")+j; stmt.executeUpdate("Update tablename set Useryue='"+j+"' where UserID='"+k+"'"); rs.close(); stmt.close(); conn.close(); return 1; } } catch(Exception sqle){ System.err.println(sqle); return 4; } } return 2; } return 3; } public static int checkUser(String k,String m) { try{ //1.注册驱动 String driverClassName = "com.mysql.jdbc.Driver"; Class.forName("com.mysql.jdbc.Driver"); //2.连接数据库 Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/ren","root",""); String temp_ID=k; String temp_pass=m; String sql_user="select userID,userPW from tablename where UserID=? and UserPW=?"; PreparedStatement pst=null; pst=conn.prepareStatement(sql_user); pst.setString (1,temp_ID); //为绑定变量赋值 pst.setString (2,temp_pass); ResultSet rst=pst.executeQuery(); if(rst.next()) { rst.close(); pst.close(); conn.close(); return 1; } else return 0; } catch(Exception sqle){ System.err.println(sqle); return 0; } } }