C3P0初学习

学习了如何使用C3P0后，经常容易忘，所以写下来以便对以后有所帮助。

1.添加jar包

使用C3P0数据源需要添加c3p0-0.9.1.2.jar，mysql-connector-java-5.0.8-bin.jar两个jar包

2.编写配置文件

使用C3P0需要编写 c3p0-config.xml 文件 ，放在java web项目中src文件夹下， 文件内容如下：

<?xml version="1.0" encoding="UTF-8"?><c3p0-config>  <default-config><property name="driverClass">com.mysql.jdbc.Driver</property><property name="jdbcUrl">jdbc:mysql://localhost:3306/123</property><property name="user">root</property><property name="password">abc</property>    <property name="initialPoolSize">10</property>    <property name="maxIdleTime">30</property>    <property name="maxPoolSize">100</property>    <property name="minPoolSize">10</property>  </default-config>  </c3p0-config>

3.编写工具类

import java.sql.Connection;import java.sql.ResultSet;import java.sql.SQLException;import java.sql.Statement;import com.mchange.v2.c3p0.ComboPooledDataSource;/** * @author: Jeson * @date:2017-12-24 下午3:08:29 * @version : *  */public class C3P0Util {private static ComboPooledDataSource datasource = new ComboPooledDataSource();public static Connection getConnection() {try {return datasource.getConnection();} catch (SQLException e) {// TODO Auto-generated catch blockthrow new RuntimeException("创建数据库连接失败……");}}public static void release(ResultSet rs, Statement stmt, Connection conn) {if (rs != null) {try {rs.close();} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}}rs = null;if (stmt != null) {try {stmt.close();} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}}stmt = null;if (conn != null) {try {conn.close();} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}}conn = null;}}