mysql驱动和druid连接池依赖配置：

 <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid</artifactId>
            <version>1.1.21</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.47</version>
        </dependency>
    </dependencies>

maven会自动导入对应的包：

xml配置Bean：

<bean class="com.alibaba.druid.pool.DruidDataSource" id="dataSource">
        <property name="username" value="root"></property>
        <property name="password" value="123456"></property>
        <property name="url" value="jdbc:mysql://localhost:3306/db1"></property>
        <property name="driverClassName" value="com.mysql.jdbc.Driver"></property>
    </bean>

 测试代码：

    /**
     * 数据库连接池
     */
    @Test
    public void fun7(){
        System.out.println("begin!");
        DruidDataSource dataSource = ioc.getBean("dataSource", DruidDataSource.class);
        System.out.println(dataSource);
    }

运行结果：

begin!
{
	CreateTime:"2022-05-28 19:57:28",
	ActiveCount:0,
	PoolingCount:0,
	CreateCount:0,
	DestroyCount:0,
	CloseCount:0,
	ConnectCount:0,
	Connections:[
	]
}

进程已结束，退出代码为 0

创建资源文件：

 内容：

mysql.username=root
mysql.password=123456
mysql.url=jdbc:mysql://localhost:3306/db1
mysql.driverClassName=com.mysql.jdbc.Driver

xml配置：

<bean class="com.alibaba.druid.pool.DruidDataSource" id="dataSource">
        <property name="username" value="${mysql.username}"></property>
        <property name="password" value="747699"></property>
        <property name="url" value="jdbc:mysql://localhost:3306/db1"></property>
        <property name="driverClassName" value="com.mysql.jdbc.Driver"></property>
    </bean>
    <context:property-placeholder location="db.properties"></context:property-placeholder>

再次运行：

begin!
{
    CreateTime:"2022-05-28 20:09:48",
    ActiveCount:0,
    PoolingCount:0,
    CreateCount:0,
    DestroyCount:0,
    CloseCount:0,
    ConnectCount:0,
    Connections:[
    ]
}

进程已结束，退出代码为 0

没有问题！