C3P0数据库连接池使用

C3P0数据库连接池使用 1、拷贝jar包：c3p0-0.9.1.2.jar c3p0-0.9.1.2-jdk1.3.jar c3p0-oracle-thin-extras-0.9.1.2.jar（oracle需要） 2、书写配制文件放在src目录下：c3p0-config.xml（名字只能是这个） 3、类C3P0Util c3p0-config.xml 内容： ?xml version

C3P0数据库连接池使用

1、拷贝jar包：c3p0-0.9.1.2.jar c3p0-0.9.1.2-jdk1.3.jar c3p0-oracle-thin-extras-0.9.1.2.jar（oracle需要）

2、书写配制文件放在src目录下：c3p0-config.xml（名字只能是这个）

3、类C3P0Util

c3p0-config.xml 内容：

<?xml version="1.0" encoding="UTF-8"?>
<c3p0-config>
    <!-- This is default config! -->
    <default-config>
        <property name="initialPoolSize">10</property>
        <property name="maxIdleTime">30</property>
        <property name="maxPoolSize">100</property>
        <property name="minPoolSize">10</property>
        <property name="maxStatements">200</property>
    </default-config>

    <!-- This is my config for mysql-->
    <named-config name="mysql">
        <property name="driverClass">com.mysql.jdbc.Driver</property>
        <property name="jdbcUrl">jdbc:mysql://localhost:3306/test</property>
        <property name="user">root</property>
        <property name="password"></property>
        <property name="initialPoolSize">10</property>
        <property name="maxIdleTime">30</property>
        <property name="maxPoolSize">100</property>
        <property name="minPoolSize">10</property>
        <property name="maxStatements">200</property>
    </named-config>


    <!-- This is my config for oracle -->
    <named-config name="oracle">
        <property name="driverClass">oracle.jdbc.driver.OracleDriver</property>
        <property name="jdbcUrl">jdbc:oracle:thin:@localhost:1521:orcl</property>
        <property name="user">scott</property>
        <property name="password">liang</property>
        <property name="initialPoolSize">10</property>
        <property name="maxIdleTime">30</property>
        <property name="maxPoolSize">100</property>
        <property name="minPoolSize">10</property>
        <property name="maxStatements">200</property>
    </named-config>
</c3p0-config>

C3P0Util:

package com.liang.util;

import java.io.InputStream;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.Properties;

import com.mchange.v2.c3p0.ComboPooledDataSource;
/**
 * 数据库工具类
 * @author liang
 *
 */
public class C3P0Util {
    static ComboPooledDataSource cpds=null;
    static{
        //这里有个优点，写好配置文件，想换数据库，简单
        //cpds = new ComboPooledDataSource("oracle");//这是oracle数据库
        cpds = new ComboPooledDataSource("mysql");//这是mysql数据库
    }
    /**
     * 获得数据库连接
     * @return   Connection
     */
    public static Connection getConnection(){
        try {
            return cpds.getConnection();
        } catch (SQLException e) {
            e.printStackTrace();
            return null;
        }
    }

    /**
     * 数据库关闭操作
     * @param conn
     * @param st
     * @param pst
     * @param rs
     */
    public static void close(Connection conn,PreparedStatement pst,ResultSet rs){
        if(rs!=null){
            try {
                rs.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
        if(pst!=null){
            try {
                pst.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }

        if(conn!=null){
            try {
                conn.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    }
    /**
     * 测试DBUtil类
     * @param args
     */
    public static void main(String[] args) {
        Connection conn=getConnection();
        System.out.println(conn.getClass().getName());
        close(conn,null,null);
    }
}