java数据库连接池c3p0初学

c3p0需要下载一个jar包(Oracle就需要多下载一个)：

c3p0-0.9.1.2.jar:
https://mvnrepository.com/artifact/c3p0/c3p0/0.9.1.2
c3p0-oracle-thin-extras-0.9.0.2.jar:
https://mvnrepository.com/artifact/c3p0/c3p0-oracle-thin-extras/0.9.0.2

不多废话,前面几篇文章有讲

	//方式一
	public static DataSource getDataSortceByC3P0(){
        ComboPooledDataSource comboPooledDataSource = new ComboPooledDataSource();
        try {
            comboPooledDataSource.setDriverClass("oracle.jdbc.driver.OracleDriver");
        } catch (PropertyVetoException e) {
            e.printStackTrace();
        }
        comboPooledDataSource.setJdbcUrl("jdbc:oracle:thin:@127.0.0.1:1521:orcl");
        comboPooledDataSource.setUser("scott");
        comboPooledDataSource.setPassword("tiger");

        return comboPooledDataSource;

    }
    //方式二
    public static DataSource getDataSortceByC3P0ByXML(){
        ComboPooledDataSource comboPooledDataSource = new ComboPooledDataSource("haha");
        return comboPooledDataSource;
    }
    public static void main(String[] args) {
        try {
            System.out.println(getDataSortceByC3P0().getConnection());
            System.out.println(getDataSortceByC3P0ByXML().getConnection());
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }

方式二需要建一个c3p0-config.xml(不要变名称,默认即可)文件,并写入以下代码:

<?xml version="1.0" encoding="UTF-8"?>
<c3p0-config>
    <!--一-->
    <defaule-config>
        <property name="user">scott</property>
        <property name="password">tiger</property>
        <property name="driverClass">oracle.jdbc.driver.OracleDriver</property>
        <property name="jdbcUrl">jdbc:oracle:thin:@127.0.0.1:1521:orcl</property>
        <property name="checkoutTimeOut">30000</property>
    </defaule-config>
    <!--二(可以认为是一的子类,程序先找二,没有再找一)-->
    <named-config name="haha">
        <property name="user">scott</property>
        <property name="password">tiger</property>
        <property name="driverClass">oracle.jdbc.driver.OracleDriver</property>
        <property name="jdbcUrl">jdbc:oracle:thin:@127.0.0.1:1521:orcl</property>
        <property name="checkoutTimeOut">20000</property>
    </named-config>
</c3p0-config>