C3P0连接池的配置与使用

1、下载c3p0-0.9.1.2.jar

下载地址：http://download.csdn.net/detail/chunxiaqiudong5/9661922

2、添加配置文件c3p0-config.xml

3、配置文件内容如下：

 xml version="1.0" encoding="UTF-8"?>
 <c3p0-config>

     <default-config>
         <property name="initialPoolSize">10property>
         <property name="maxIdleTime">30property>
         <property name="maxPoolSize">100property>
         <property name="minPoolSize">10property>
         <property name="maxStatements">200property>
     default-config>


     <named-config name="mysql">
         <property name="driverClass">com.mysql.jdbc.Driverproperty>
         <property name="jdbcUrl">jdbc:mysql://localhost:3306/jdbc?useUnicode=true&characterEncoding=UTF8property>
         <property name="user">rootproperty>
         <property name="password">property>

         <property name="initialPoolSize">10property>

         <property name="maxIdleTime">30property>

         <property name="maxPoolSize">100property>

         <property name="minPoolSize">10property>

         <property name="maxStatements">200property>

         <property name="checkoutTimeout" value="3000"/>

         <property name="acquireIncrement" value="2"/>

         <property name="acquireRetryAttempts" value="0"/>

         <property name="acquireRetryDelay" value="1000" />

         <property name="autoCommitOnClose">falseproperty>

         <property name="automaticTestTable">Testproperty>

         <property name="breakAfterAcquireFailure">falseproperty>

         <property name="idleConnectionTestPeriod">60property>

         <property name="maxStatementsPerConnection">property>
     named-config>



     <named-config name="oracle">
         <property name="driverClass">oracle.jdbc.driver.OracleDriverproperty>
         <property name="jdbcUrl">jdbc:oracle:thin:@localhost:1521:orclproperty>
         <property name="user">scottproperty>
         <property name="password">liangproperty>
         <property name="initialPoolSize">10property>
         <property name="maxIdleTime">30property>
         <property name="maxPoolSize">100property>
         <property name="minPoolSize">10property>
         <property name="maxStatements">200property>
     named-config>
 c3p0-config>

4、连接池连接类

 package com.xxx.utils;

 import java.sql.Connection;
 import java.sql.SQLException;

 import javax.sql.DataSource;

 import com.mchange.v2.c3p0.ComboPooledDataSource;

 public class JDBCUtil {

     private static DataSource dataSource=null;
     static{
         dataSource=new ComboPooledDataSource("mysql");
     }

     /**
      * 获取数据库连接
      * @return
      */
     public static Connection getConnection(){
         Connection conn=null;
         try {
              conn=dataSource.getConnection();
         } catch (SQLException e) {
             e.printStackTrace();
         }
         return conn;
     }


     /**
      * 关闭数据库连接
      * @param conn
      */
     public static void closeConn(Connection conn){
         try {
             if(conn!=null && conn.isClosed()){
                 conn.close();
             }
         } catch (SQLException e) {
             e.printStackTrace();
         }
     }
 }

5、测试

 package com.xxx.test;

 import java.sql.Connection;
 import java.sql.PreparedStatement;
 import java.sql.ResultSet;
 import java.sql.SQLException;

 import org.junit.Test;

 import com.xxx.utils.JDBCUtil;

 public class TestJdbc {

     @Test
     public void test() {
         Connection conn=JDBCUtil.getConnection();
         System.out.println(conn);
         try {
             PreparedStatement stmt=conn.prepareStatement("select * from tb_user");
             ResultSet re=stmt.executeQuery();
             while(re.next()){
                 String name=re.getString(2);
                 System.out.println(name);

             }


         } catch (SQLException e) {
             // TODO Auto-generated catch block
             e.printStackTrace();
         }
     }



 }