AI专业者开发社区 1 号成员
  •  0 回帖  •  7 浏览  •  4 个月前
 

java连数据库和数据库连接池踩坑日记（二）-------数据库连接池c3p0

　　关于数据库连接池，我觉得有些沮丧，因为最后被毙掉了说不用考虑多线程的问题……

　　数据库连接池的推荐：https://www.cnblogs.com/nuccch/p/8120349.html

　　我最终选择的是 c3p0，不过找不到最详细的那份教程了，也解决不了如何去掉 log4j 的 warn 日志的问题。

　　断网了，丢记录了不想记录了……

一、配置 maven 文件

        <!-- c3p0 连接池 -->
        <dependency>
            <groupId>com.mchange</groupId>
            <artifactId>c3p0</artifactId>
            <version>0.9.5.2</version>
        </dependency>

二、配置账号密码信息

我选择的是使用 xml 配置文件，放在 src/main/resources 文件夹下面

<c3p0-config>
    <!-- 默认数据源 -->
    <default-config>
        <property name="driverClass">com.mysql.jdbc.Driver</property>
        <property name="jdbcUrl">jdbc:mysql://localhost:3306?useSSL=false</property>
        <property name="user">root</property>
        <property name="password">123456</property>
        <property name="minPoolSize">3</property>
        <property name="maxPoolSize">10</property>
        <property name="acquireIncrement">5</property>

<span style="color: rgba(0, 0, 255, 1)">&lt;/</span><span style="color: rgba(128, 0, 0, 1)">default-config</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>


<span style="color: rgba(0, 128, 0, 1)">&lt;!--</span><span style="color: rgba(0, 128, 0, 1)"> 定义带名称的数据源 </span><span style="color: rgba(0, 128, 0, 1)">--&gt;</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">named-config </span><span style="color: rgba(255, 0, 0, 1)">name</span><span style="color: rgba(0, 0, 255, 1)">="OracleDataSource"</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
    <span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">property </span><span style="color: rgba(255, 0, 0, 1)">name</span><span style="color: rgba(0, 0, 255, 1)">="driverClass"</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>oracle.jdbc.driver.OracleDriver<span style="color: rgba(0, 0, 255, 1)">&lt;/</span><span style="color: rgba(128, 0, 0, 1)">property</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
    <span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">property </span><span style="color: rgba(255, 0, 0, 1)">name</span><span style="color: rgba(0, 0, 255, 1)">="jdbcUrl"</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>jdbc:oracle:thin:@oracle的ip地址:端口号:服务名<span style="color: rgba(0, 0, 255, 1)">&lt;/</span><span style="color: rgba(128, 0, 0, 1)">property</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
    <span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">property </span><span style="color: rgba(255, 0, 0, 1)">name</span><span style="color: rgba(0, 0, 255, 1)">="user"</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>账号<span style="color: rgba(0, 0, 255, 1)">&lt;/</span><span style="color: rgba(128, 0, 0, 1)">property</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
    <span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">property </span><span style="color: rgba(255, 0, 0, 1)">name</span><span style="color: rgba(0, 0, 255, 1)">="password"</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>密码<span style="color: rgba(0, 0, 255, 1)">&lt;/</span><span style="color: rgba(128, 0, 0, 1)">property</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
    <span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">property </span><span style="color: rgba(255, 0, 0, 1)">name</span><span style="color: rgba(0, 0, 255, 1)">="minPoolSize"</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>3<span style="color: rgba(0, 0, 255, 1)">&lt;/</span><span style="color: rgba(128, 0, 0, 1)">property</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
    <span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">property </span><span style="color: rgba(255, 0, 0, 1)">name</span><span style="color: rgba(0, 0, 255, 1)">="maxPoolSize"</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>11<span style="color: rgba(0, 0, 255, 1)">&lt;/</span><span style="color: rgba(128, 0, 0, 1)">property</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
    <span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">property </span><span style="color: rgba(255, 0, 0, 1)">name</span><span style="color: rgba(0, 0, 255, 1)">="acquireIncrement"</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>5<span style="color: rgba(0, 0, 255, 1)">&lt;/</span><span style="color: rgba(128, 0, 0, 1)">property</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;/</span><span style="color: rgba(128, 0, 0, 1)">named-config</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>



</c3p0-config>

三、java 中调用

try {
    private DataSource ds;
    // ds = new ComboPooledDataSource(); //本地 mysql
    ds = new ComboPooledDataSource("OracleDataSource"); //oracle
    Connection connection = ds.getConnection();
    //得到 connection 后可进行 sql 操作了
} catch (SQLException e) {e.printStackTrace();
}

四、多线程调用数据库连接池

参考