Add jdbc connection pool in apache tomcat

Modify context.xml file that can be found in this directory $TOMCAT_HOME/conf/context.xml

<Context>

    <!-- ... -->

    <!-- maxActive: Maximum number of dB connections in pool. Make sure you
         configure your mysqld max_connections large enough to handle
         all of your db connections. Set to -1 for no limit.
         -->

    <!-- maxIdle: Maximum number of idle dB connections to retain in pool.
         Set to -1 for no limit.  See also the DBCP documentation on this
         and the minEvictableIdleTimeMillis configuration parameter.
         -->

    <!-- maxWait: Maximum time to wait for a dB connection to become available
         in ms, in this example 10 seconds. An Exception is thrown if
         this timeout is exceeded.  Set to -1 to wait indefinitely.
         -->

    <!-- username and password: MySQL dB username and password for dB connections  -->

    <!-- Class name for the official MySQL Connector/J driver is com.mysql.jdbc.Driver. -->
    
    <!-- url: The JDBC connection url for connecting to your MySQL DB -->

  <Resource name="jdbc/JNDI_dataSource_name" auth="Container" type="javax.sql.DataSource"
               maxActive="100" maxIdle="30" maxWait="10000"
               username="example_DB_username" password="example_DB_password" driverClassName="com.mysql.jdbc.Driver"
               url="jdbc:mysql://localhost:3306/example_DB_name"/>

    <!-- ... -->

</Context>