struts令牌token实例

package com.yourcompany.bean; import java.io.*; import java.util.*; import java.sql.*; public class DBConnection { /* 数据访问组件 */ private static DBConnection instance = null; //取得连接 public static synchronized Connection getConnection() { if (instance == null){ instance = new DBConnection(); } return instance._getConnection(); } private DBConnection(){ super(); } /** * 创建连接 * @return */ private Connection _getConnection(){ try{ String sDBDriver = null; String sConnection = null; String sUser = null; String sPassword = null; Properties p = new Properties(); InputStream is = getClass().getResourceAsStream("/com/yourcompany/struts/db.properties"); p.load(is); sDBDriver = p.getProperty("DBDriver",sDBDriver); sConnection = p.getProperty("Connection",sConnection); sUser = p.getProperty("User",""); sPassword = p.getProperty("Password",""); Properties pr = new Properties(); pr.put("user",sUser); pr.put("password",sPassword); pr.put("characterEncoding", "GB2312"); pr.put("useUnicode", "TRUE"); Class.forName(sDBDriver).newInstance(); return DriverManager.getConnection(sConnection,pr); } catch(Exception se){ System.out.println(se); return null; } } /** * 根据sql语句返回一个结果集 */ public static ResultSet getResultSet(String sql) throws SQLException{ return DBConnection.getConnection().createStatement().executeQuery(sql); } /** * 根据sql语句返回一个整型，主要用于增加，删除，修改 */ public static int getSql(String sql) throws Exception{ return DBConnection.getConnection().createStatement().executeUpdate(sql); } /** * * @param ps * @param rs */ public static void clearConn(PreparedStatement ps,ResultSet rs){ closeResultSet(rs); closePreparedStatement(ps); } public static void clearConn(PreparedStatement ps,Connection con){ //closeResultSet(rs); closePreparedStatement(ps); freeConncetion(con); } public static void clearConn(Connection con, PreparedStatement ps,ResultSet rs){ closeResultSet(rs); closePreparedStatement(ps); freeConncetion(con); } /** * 释放连接池中的所有Connection * * @throws SQLException */ public static void freeConncetion(Connection conn){ try{ if(conn != null) conn.close(); }catch(SQLException Ex_Connection){ System.out.println("SQLException when close Connection. "+Ex_Connection); } } /** * 释放连接池中的所有ResultSet * * @throws SQLException */ public static void closeResultSet(ResultSet resultset){ try{ if(resultset != null) resultset.close(); }catch(SQLException Ex_Resultset){ System.out.println("SQLException when close ResultSet. "+Ex_Resultset); } } /** * 释放连接池中的所有PreparedStatement * * @throws SQLException */ public static void closePreparedStatement(PreparedStatement ps){ try { if (ps != null) ps.close(); } catch (SQLException Ex_Statement) { System.out.println("SQLException when close PreparedStatement."+Ex_Statement); } } public static void rollBack(Connection conn) { try{ conn.rollback(); }catch(SQLException se){ System.out.println("SQLException when close rollBack."+se); } } public static void main(String[] args) { Connection conn=DBConnection.getConnection(); System.out.print(conn); // TODO 自动生成方法存根 } }