jsp+Servlet利用mvc模式写的一个图书馆管理系统(源码带sql文件)

package com.biyeseng.db; import java.sql.Connection; import java.sql.DriverManager; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.util.Properties; /** * 数据库管理类 * @author biyeseng * @company www.biyeseng.cn * */ public class DBManager { public static final String DEFAULT_DRIVER_NAME = "com.mysql.jdbc.Driver"; public static final String DEFAULT_DB_URL = "jdbc:mysql://localhost:3306/tsgglxt?useUnicode=true&characterEncoding=UTF-8"; public static String DB_URL = null; public static Properties prop = null; // 获取数据连接 public Connection getConnection() { Connection coon = null; try { Class.forName(DEFAULT_DRIVER_NAME); coon = DriverManager.getConnection(DEFAULT_DB_URL, "root", "123456"); } catch (Exception e) { e.printStackTrace(); } return coon; } public static void main(String[] args) { DBManager manager = new DBManager(); manager.getConnection(); } public String login(String username, String pwd) { Connection coon = getConnection(); ResultSet rs = null; PreparedStatement pstmt = null; try { pstmt = coon .prepareStatement("select * from admin where userName='" + username + "' and userPw='" + pwd + "'"); rs = pstmt.executeQuery(); while (rs.next()) { return rs.getString("type"); } } catch (SQLException e) { e.printStackTrace(); } finally { try { if (pstmt != null) pstmt.close(); if (coon != null) coon.close(); } catch (Exception e) { e.printStackTrace(); } } return null; } public String loginYH(String username, String pwd) { Connection coon = getConnection(); ResultSet rs = null; PreparedStatement pstmt = null; try { pstmt = coon.prepareStatement("select * from hui where card='" + username + "' and pass='" + pwd + "'"); rs = pstmt.executeQuery(); while (rs.next()) { return rs.getString("name") + ":" + rs.getString("state"); } } catch (SQLException e) { e.printStackTrace(); } finally { try { if (pstmt != null) pstmt.close(); if (coon != null) coon.close(); } catch (Exception e) { e.printStackTrace(); } } return null; } public boolean hasId(String goodsid) { Connection coon = getConnection(); ResultSet rs = null; PreparedStatement pstmt = null; try { pstmt = coon.prepareStatement("select * from kucun where goodsid='" + goodsid + "'"); rs = pstmt.executeQuery(); while (rs.next()) { return true; } } catch (SQLException e) { e.printStackTrace(); } finally { try { if (pstmt != null) pstmt.close(); if (coon != null) coon.close(); } catch (Exception e) { e.printStackTrace(); } } return false; } public static String TextToHtml(String sourcestr) { int strlen; String restring = "", destr = ""; strlen = sourcestr.length(); for (int i = 0; i < strlen; i++) { char ch = sourcestr.charAt(i); switch (ch) { case '<': destr = "<"; break; case '>': destr = ">"; break; case '\"': destr = "\""; break; case '&': destr = "&"; break; case 13: destr = "<br>"; break; case 32: destr = "&nbsp;"; break; default: destr = "" + ch; break; } restring = restring + destr; } return "" + restring; } }