MySql DBUtil

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 {public static Connection createConn(){Connection conn = null;try {Class.forName("com.mysql.jdbc.Driver");conn = DriverManager.getConnection("jdbc:mysql://localhost/bbs2009","root","填写密码");} catch (SQLException e){e.printStackTrace();} catch (ClassNotFoundException e) {    e.printStackTrace();    }return conn;}public static PreparedStatement Prepare(Connection conn,String sql){PreparedStatement ps = null;try {ps= conn.prepareStatement(sql);} catch (SQLException e) {e.printStackTrace();}return ps;}public static void close(Connection conn){if(conn ==null) return; try {conn.close();conn = null;} catch (SQLException e) {e.printStackTrace();}}public static void close(Statement stmt){try {stmt.close();stmt =null;} catch (SQLException e) {e.printStackTrace();}}public static void close(ResultSet rs){try {rs.close();rs=null;} catch (SQLException e) {e.printStackTrace();} }}