Java使用C3P0數(shù)據(jù)源鏈接數(shù)據(jù)庫(kù)

更新時(shí)間：2019年08月21日 11:45:02 作者：1512326654

這篇文章主要為大家詳細(xì)介紹了Java使用C3P0數(shù)據(jù)源鏈接數(shù)據(jù)庫(kù)，具有一定的參考價(jià)值，感興趣的小伙伴們可以參考一下

本文實(shí)例為大家分享了Java使用C3P0數(shù)據(jù)源鏈接數(shù)據(jù)庫(kù)的具體代碼，供大家參考，具體內(nèi)容如下

1、相關(guān)jar包，這里需要3個(gè)jar包

2、具體鏈接數(shù)據(jù)庫(kù)代碼

ComboPooledDataSource類繼承自AbstractComboPooledDataSource類，且AbstractComboPooledDataSource類實(shí)現(xiàn)了PooledDataSource接口

ComboPooledDataSource常用方法

（1）、通過ComboPooledDataSource類直接創(chuàng)建數(shù)據(jù)源對(duì)象

Example4.java

import com.mchange.v2.c3p0.ComboPooledDataSource;
import javax.sql.DataSource;
import java.sql.SQLException;
public class Example4{
  public static DataSource dataSource = null;
  //初始化C3P0數(shù)據(jù)源
  static {
    ComboPooledDataSource comboPooledDataSource = new ComboPooledDataSource();
    try{
      comboPooledDataSource.setDriverClass("com.mysql.jdbc.Driver");
      comboPooledDataSource.setJdbcUrl("jdbc:mysql://127.0.0.1:3306/chapter02");
      comboPooledDataSource.setUser("root");
      comboPooledDataSource.setPassword("1234");
      //初始化
      comboPooledDataSource.setInitialPoolSize(5);
      //設(shè)置最大的鏈接數(shù)
      comboPooledDataSource.setMaxPoolSize(15);
      dataSource = comboPooledDataSource;
    }catch (Exception e){
    }
  }
  public static void main(String[] args)throws SQLException {
    System.out.println(dataSource.getConnection());
  }
}

（2）、通過配置文件創(chuàng)建數(shù)據(jù)源對(duì)象

在項(xiàng)目的src目錄下創(chuàng)建一個(gè)出c3p0-donfig.xml文件

c3p0-donfig.xml內(nèi)容如下

<?xml version="1.0" encoding="utf-8" ?>
<c3p0-config>
  <default-config>
    <property name="user">root</property>
    <property name="password">1234</property>
    <property name="driverClass">com.mysql.jdbc.Driver</property>
    <property name="jdbcUrl">
      jdbc:mysql://localhost:3306/chapter02
    </property>
    <property name="checkoutTimeout">30000</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>
  </default-config>
  <named-config name="dongyao">
    <property name="initialPoolSize">5</property>
    <property name="maxPoolSize">15</property>
    <property name="driverClass">com.mysql.jdbc.Driver</property>
    <property name="jdbcUrl">
      jdbc:mysql://localhost:3306/chapter02
    </property>
    <property name="user">root</property>
    <property name="password">1234</property>
  </named-config>
</c3p0-config>

其中<default-config>是默認(rèn)配置，<named-config name=””>是自定義配置，一個(gè)配置文件中可以有一個(gè)或者多個(gè)自定義配置，調(diào)用ComboPoolDataSource(String configName)方法傳入<named-config>節(jié)點(diǎn)中name屬性的值即可創(chuàng)建C3P0數(shù)據(jù)源對(duì)象。

在項(xiàng)目的src目錄下創(chuàng)建一個(gè)Example5的類

Example5.java

import com.mchange.v2.c3p0.ComboPooledDataSource;
 
import javax.sql.DataSource;
import java.sql.SQLException;
 
public class Example5 {
  public static DataSource dataSource = null;
  static {
    ComboPooledDataSource comboPooledDataSource = new ComboPooledDataSource("dongyao");
    dataSource = comboPooledDataSource;
  }
  public static void main(String[] args) throws SQLException {
    System.out.println(dataSource.getConnection());
  }
}

3、控制臺(tái)顯示