在线投票系统（jsp）

package com.yxq.toolbean; import java.sql.Connection; import java.sql.DriverManager; import java.sql.Statement; import java.sql.ResultSet; import java.util.ArrayList; import java.util.List; import com.yxq.valuebean.TempSingle; import com.yxq.valuebean.VoteSingle; public class DB { private String className; private String url; private String username; private String password; private Connection con; private Statement stm; private ResultSet rs; public DB() { className = "com.microsoft.jdbc.sqlserver.SQLServerDriver"; url = "jdbc:microsoft:sqlserver://localhost:1433;databaseName=db_vote"; username = "sa"; password = ""; } /** * @功能 加载数据库驱动程序 */ public void loadDrive() { try { Class.forName(className); } catch (ClassNotFoundException e) { System.out.println("加载数据库驱动程序失败！"); e.printStackTrace(); } } /** * @功能 获取数据库连接 */ public void getCon() { loadDrive(); try { con = DriverManager.getConnection(url, username, password); } catch (Exception e) { System.out.println("连接数据库失败！"); e.printStackTrace(); } } /** * @功能 获取Statement对象 */ public void getStm() { getCon(); try { stm = con.createStatement(); } catch (Exception e) { System.out.println("获取Statement对象失败！"); e.printStackTrace(); } } /** * @功能 查询数据表，获取结果集 */ public void getRs(String sql) { getStm(); try { rs = stm.executeQuery(sql); } catch (Exception e) { System.out.println("查询数据库失败！"); e.printStackTrace(); } } /** * @功能 查询数据表，获取投票选项 */ public List selectVote(String sql) { List votelist = null; if (sql != null && !sql.equals("")) { getRs(sql); if (rs != null) { votelist = new ArrayList(); try { while (rs.next()) { VoteSingle voteSingle = new VoteSingle(); voteSingle.setId(MyTools.intToStr(rs.getInt(1))); voteSingle.setTitle(rs.getString(2)); voteSingle.setNum(MyTools.intToStr(rs.getInt(3))); voteSingle.setOrder(MyTools.intToStr(rs.getInt(4))); votelist.add(voteSingle); } } catch (Exception e) { System.out.println("封装tb_vote表中数据失败！"); e.printStackTrace(); } finally { closed(); } } } return votelist; } /** * @功能 查询数据表，获取指定IP最后一次投票的记录 */ public TempSingle selectTemp(String sql) { TempSingle tempSingle = null; if (sql != null && !sql.equals("")) { getRs(sql); if (rs != null) { try { while (rs.next()) { tempSingle = new TempSingle(); tempSingle.setId(MyTools.intToStr(rs.getInt(1))); tempSingle.setVoteIp(rs.getString(2)); tempSingle.setVoteMSEL(rs.getLong(3)); tempSingle.setVoteTime(rs.getString(4)); } } catch (Exception e) { System.out.println("封装tb_temp表中数据失败！"); e.printStackTrace(); } finally { closed(); } } } return tempSingle; } /** * @功能 更新数据表 */ public int update(String sql) { int i = -1; if (sql != null && !sql.equals("")) { getStm(); try { i = stm.executeUpdate(sql); } catch (Exception e) { System.out.println("更新数据库失败！"); e.printStackTrace(); } finally { closed(); } } return i; } /** * @功能 关闭数据库连接 */ public void closed() { try { if (rs != null) rs.close(); if (stm != null) stm.close(); if (con != null) con.close(); } catch (Exception e) { System.out.println("关闭数据库失败！"); e.printStackTrace(); } } }