JSP开发的一个论坛程序

package com.tyy.bbs; import java.sql.Connection; import java.sql.DriverManager; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; public class DB { // private Connection conn; // public DB() { // try { // Class.forName("com.mysql.jdbc.Driver"); // conn = DriverManager.getConnection("jdbc:mysql://localhost/tyy", // "root", "passwd"); // } catch (Exception e) { // e.printStackTrace(); // } // } public static Connection getConnection() { Connection conn = null; try { Class.forName("com.mysql.jdbc.Driver"); conn = DriverManager.getConnection("jdbc:mysql://localhost/bbs", "root", "passwd"); } catch (Exception e) { e.printStackTrace(); } return conn; } public static Statement getStatement(Connection conn) { Statement stmt = null; try { stmt = conn.createStatement(); } catch (SQLException e) { e.printStackTrace(); } return stmt; } public static ResultSet getResultSet(Statement stmt, String sql) { ResultSet rs = null; try { rs = stmt.executeQuery(sql); } catch (SQLException e) { e.printStackTrace(); } return rs; } public static int executeUpdate(Connection conn, String sql) { int count = 0; try { Statement stmt = conn.createStatement(); count = stmt.executeUpdate(sql); } catch (SQLException e) { e.printStackTrace(); } return count; } public static PreparedStatement prepareStatement(Connection conn, String sql) { PreparedStatement pstmt = null; try { pstmt = conn.prepareStatement(sql); } catch (SQLException e) { e.printStackTrace(); } return pstmt; } public static PreparedStatement prepareStatement(Connection conn, String sql, int autoGeneratedKeys) { PreparedStatement pstmt = null; try { pstmt = conn.prepareStatement(sql, autoGeneratedKeys); } catch (Exception e) { e.printStackTrace(); } return pstmt; } public static void close(Connection conn) { if (conn != null) { try { conn.close(); conn = null; } catch (SQLException e) { e.printStackTrace(); } } } public static void close(Statement stmt) { if (stmt != null) { try { stmt.close(); } catch (SQLException e) { e.printStackTrace(); } stmt = null; } } public static void close(ResultSet rs) { if (rs != null) { try { rs.close(); rs = null; } catch (SQLException e) { e.printStackTrace(); } } } }