class JdbcutilsTest {

    @Test

    void TestGetConnection() {

        Connection conn = Jdbcutils.getConnection();

        System.out.println(conn);

    }

}

<?xml version="1.0" encoding="UTF-8"?>

<c3p0-config>

    <!-- 默认配置，如果没有指定则使用这个配置 -->

    <default-config>

        <property name="driverClass">com.mysql.cj.jdbc.Driver</property>

        <property name="jdbcUrl">

            <![CDATA[jdbc:mysql://localhost:3306/mvcproject?useUnicode=true&characterEncoding=utf8&use=true&useSSL=false&serverTimezone=GMT]]>

        </property>

        <property name="user">root</property>

        <property name="password">XXXXXXX</property>

        <!-- 初始化池大小 -->

        <property name="initialPoolSize">2</property>

        <!-- 最大空闲时间 -->

        <property name="maxIdleTime">30</property>

        <!-- 最多有多少个连接 -->

        <property name="maxPoolSize">10</property>

        <!-- 最少几个连接 -->

        <property name="minPoolSize">2</property>

        <!-- 每次最多可以执行多少个批处理语句 -->

        <property name="maxStatements">50</property>

    </default-config>

    <!-- 命名的配置 -->

    <named-config name="BarryLee">

        <property name="driverClass">com.mysql.cj.jdbc.Driver</property>

        <property name="jdbcUrl"><![CDATA[jdbc:mysql://localhost:3306/mvcproject?useUnicode=true&characterEncoding=utf8&use=true&useSSL=false&serverTimezone=GMT]]></property>

        <property name="user">root</property>

        <property name="password">XXXXXX</property>

        <property name="acquireIncrement">5</property><!-- 如果池中数据连接不够时一次增长多少个 -->

        <property name="initialPoolSize">100</property>

        <property name="minPoolSize">50</property>

        <property name="maxPoolSize">1000</property>

        <property name="maxStatements">0</property>

        <property name="maxStatementsPerConnection">5</property> <!-- he's important, but there's only one of him -->

    </named-config>

</c3p0-config>

具体给我的警告：

Establishing SSL connection without server's identity verification is not recommended. According to MySQL 5.5.45+, 5.6.26+ and 5.7.6+ requirements SSL connection must be established by default if explicit option isn't set. For compliance with existing applications not using SSL the verifyServerCertificate property is set to 'false'. You need either to explicitly disable SSL by setting useSSL=false, or set useSSL=true and provide truststore for server certificate verification.

翻译之后：根据MySQL5.5.45+、5.6.26+和5.7.6+的要求，如果不设置显式选项，则默认必须建立SSL连接。为了符合不使用SSL的现有应用程序，verifyServerCertificate属性设置为“false”。您需要通过设置useSSL=false显式禁用SSL，或者设置useSSL=true并提供用于服务器证书验证的信任库。

发现是在jdbcUrl里面缺了东西，必须要禁用SSL，也就是useSSL=false；

接下来继续运行便有了第三个错误：com.mchange.v2.resourcepool.CannotAcquireResourceException：A ResourcePool could not acquire a resource from its primary factory or source.

com.mysql.cj.jdbc.Driver
和之前的相比

com.mysql.jdbc.Driver

还有就是我password输错了，好在发现了。