c3p0 一个数据库链接的例子

  1 public class testMysql implements myRoot{
  2     private ComboPooledDataSource dataSource = null;
  3 //    private Connection connection = null;
  4     @Override
  5     public void done() {
  6         initMysql();
  7         
  8         Connection connection = getConnection();//获取自动提交数据库连接
  9         setAutoCommit(connection, true);
 10         
 11         String name = doSql(connection, String.class, "select playerName from t_player where playerId = ?", 2);
 12         System.out.println("name = " + name);
 13         
 14         tplayer player = doSql(connection, tplayer.class, "select * from t_player where playerId = ?", 2);
 15         
 16         System.out.println("getPlayerId = " + player.getPlayerId());
 17         System.out.println("getPlayerName = " + player.getPlayerName());
 18         System.out.println("getCreateTime = " + player.getCreateTime());
 19         System.out.println("getLoginTime = " + player.getLoginTime());
 20         System.out.println("getLogoutTime = " + player.getLogoutTime());
 21         
 22         //--------批量提交sql-------------
 23         
 24         String Ary[] = new String[2];
 25         Ary[0] = "UPDATE t_player SET playerName = \"ccc\" WHERE playerId = 3;";
 26         Ary[1] = "UPDATE t_player SET playerName = \"ddd\" WHERE playerId = 4;";
 27         
 28         batchSql(connection, Ary);
 29         closeConnection(connection);//关闭连接
 30         
 31     }
 32     //批量提交处理事务
 33     public void batchSql(Connection connection, String []Ary){
 34         Statement st = null;
 35         try {
 36             setAutoCommit(connection, false);//必须为false,否则java.sql.SQLException: Can‘t call commit when autocommit=true
 37             st = connection.createStatement();
 38             
 39             int c=0;
 40             for(String sql:Ary){
 41                 st.addBatch(sql);
 42                 c++;
 43                 if(c == 1000){//防止内存溢出，一次不要提交太多条,暂设1000条
 44                     st.executeBatch();
 45                     commit(connection);
 46                     st.clearBatch();
 47                     c=0;
 48                 }
 49                 if(c>0){
 50                     st.executeBatch();
 51                     commit(connection);
 52                     st.clearBatch();
 53                 }
 54             }
 55             
 56         } catch (SQLException e) {
 57             e.printStackTrace();
 58         }finally{
 59             setAutoCommit(connection, true);
 60             closeStateMent(st);
 61         }
 62     }
 63     
 64     /**
 65      * @param cls 返回类型类
 66      * @param sql sql语句
 67      * @param paramter sql语句参数
 68      * @return cls实例
 69      */
 70     @SuppressWarnings("unchecked")
 71     public <T>T doSql(Connection connection, Class<?> cls, String sql, Object... paramter){
 72         PreparedStatement pst = null;
 73         ResultSet rs = null;
 74         
 75         Object obj = null;
 76         try {
 77             pst = connection.prepareStatement(sql);//创建一个 PreparedStatement 对象来将参数化的 SQL 语句发送到数据库
 78             if(paramter != null && paramter.length  > 0){
 79                 int i=1;//从1开始
 80                 for(Object parm: paramter){
 81                     pst.setObject(i++, parm);//为sql语句设置参数 
 82                 }
 83             }
 84             rs = pst.executeQuery();//执行语句，返回ResultSet结果
 85             while(rs.next()){
 86                 if(cls.getSimpleName().toLowerCase().equals("string")){//标准类型
 87                     obj = rs.getString(1);
 88                 }else{//自定义类型
 89                     obj = cls.newInstance();//创建自定义类型
 90                     ResultSetMetaData resultsetmetadata = rs.getMetaData();//整行列信息
 91                     int count = resultsetmetadata.getColumnCount();//列数量
 92                     for(int i=1; i<=count; i++){//从1开始
 93                         String columnlabel = resultsetmetadata.getColumnLabel(i);//当前列标头
 94                         String methName = "set" + columnlabel.substring(0, 1).toUpperCase() + columnlabel.substring(1);//自定义类型的方法名，次数为set方法
 95                         
 96                         Method[] methods = cls.getDeclaredMethods();//自定义类型的方法数组
 97                         int methodsSize = methods.length;//方法数量
 98                         for(int j=0; j<methodsSize; j++){
 99                             if(methods[j].getName().equals(methName)){
100                                 Parameter[] parameterAry = methods[j].getParameters();//获取方法参数数组
101                                 Class<?> type = parameterAry[0].getType();//第一个参数类型 从0开始
102                                 String typeName = type.getSimpleName().toLowerCase();//参数类型的名字
103 //                                String typeName = methods[j].getParameters()[0].getType().getSimpleName().toLowerCase();//这种写法不被推荐
104                                 //反射调用
105                                 if(typeName.equals("int")){
106                                     methods[j].invoke(obj, rs.getInt(i));
107                                 }else if(typeName.equals("string")){
108                                     methods[j].invoke(obj, rs.getString(i));
109                                 }
110                             }
111                         }
112                     }
113                 }
114             }
115         } catch (Exception e) {
116             e.printStackTrace();
117         }finally{
118             try {
119                 if(pst != null){ pst.close(); }
120                 if( rs != null){ rs.close();  }
121             } catch (SQLException e) {
122                 e.printStackTrace();
123             }
124         }
125         return (T) obj;
126     }
127     public void initMysql(){
128         
129         dataSource = new ComboPooledDataSource();
130         try {
131             dataSource.setDriverClass("com.mysql.jdbc.Driver");//com.mysql.jdbc.Driver
132         } catch (PropertyVetoException e) {
133             e.printStackTrace();
134         }
135         dataSource.setJdbcUrl("jdbc:mysql://192.168.50.229:3306/banzhan_tplayer?autoReconnect=true&rewriteBatchedStatements=true&useUnicode=true&characterEncoding=utf-8&useSSL=false");//
136         dataSource.setUser("root");//root
137         dataSource.setPassword("123456");//123456
138         dataSource.setInitialPoolSize(1);//5 数量机器相关
139         dataSource.setMinPoolSize(1);
140         dataSource.setMaxPoolSize(1);
141         dataSource.setTestConnectionOnCheckin(true);        //每次获取connection测试其有效性
142         dataSource.setAutomaticTestTable("C3P0TestTable");    //测试表
143         dataSource.setIdleConnectionTestPeriod(360);        //每N秒检查一次空闲连接
144         dataSource.setMaxIdleTime(720);    
145     }
146     
147     public Connection getConnection(){
148         Connection connection = null;
149         if(dataSource != null){
150             try {
151                 connection =  dataSource.getConnection();
152             } catch (SQLException e) {
153                 e.printStackTrace();
154             }
155         }
156         return connection;
157     }
158     
159     public void setAutoCommit(Connection connection, boolean autoCommit){
160         
161         try {
162             connection.setAutoCommit(autoCommit);
163         } catch (SQLException e) {
164             e.printStackTrace();
165         }
166         
167     }
168     
169     public void commit(Connection connection){
170         try {
171             connection.commit();
172         } catch (SQLException e) {
173             e.printStackTrace();
174         }
175     }
176     public void closeStateMent(Statement pst){
177         if(pst != null){
178             try {
179                 pst.close();
180             } catch (SQLException e) {
181                 e.printStackTrace();
182             }
183         }
184     }
185     
186     public void closeConnection(Connection connection){
187         try {
188             if(connection != null){
189                 connection.close();
190             }
191         } catch (SQLException e) {
192             e.printStackTrace();
193         }
194     }
195 }